1
|
Sonavane M, Almeida JR, Rajan E, Williams HF, Townsend F, Cornish E, Mitchell RD, Patel K, Vaiyapuri S. Intramuscular Bleeding and Formation of Microthrombi during Skeletal Muscle Damage Caused by a Snake Venom Metalloprotease and a Cardiotoxin. Toxins (Basel) 2023; 15:530. [PMID: 37755956 PMCID: PMC10536739 DOI: 10.3390/toxins15090530] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Revised: 08/01/2023] [Accepted: 08/21/2023] [Indexed: 09/28/2023] Open
Abstract
The interactions between specific snake venom toxins and muscle constituents are the major cause of severe muscle damage that often result in amputations and subsequent socioeconomic ramifications for snakebite victims and/or their families. Therefore, improving our understanding of venom-induced muscle damage and determining the underlying mechanisms of muscle degeneration/regeneration following snakebites is critical to developing better strategies to tackle this issue. Here, we analysed intramuscular bleeding and thrombosis in muscle injuries induced by two different snake venom toxins (CAMP-Crotalus atrox metalloprotease (a PIII metalloprotease from the venom of this snake) and a three-finger toxin (CTX, a cardiotoxin from the venom of Naja pallida)). Classically, these toxins represent diverse scenarios characterised by persistent muscle damage (CAMP) and successful regeneration (CTX) following acute damage, as normally observed in envenomation by most vipers and some elapid snakes of Asian, Australasian, and African origin, respectively. Our immunohistochemical analysis confirmed that both CAMP and CTX induced extensive muscle destruction on day 5, although the effects of CTX were reversed over time. We identified the presence of fibrinogen and P-selectin exposure inside the damaged muscle sections, suggesting signs of bleeding and the formation of platelet aggregates/microthrombi in tissues, respectively. Intriguingly, CAMP causes integrin shedding but does not affect any blood clotting parameters, whereas CTX significantly extends the clotting time and has no impact on integrin shedding. The rates of fibrinogen clearance and reduction in microthrombi were greater in CTX-treated muscle compared to CAMP-treated muscle. Together, these findings reveal novel aspects of venom-induced muscle damage and highlight the relevance of haemostatic events such as bleeding and thrombosis for muscle regeneration and provide useful mechanistic insights for developing better therapeutic interventions.
Collapse
Affiliation(s)
- Medha Sonavane
- School of Pharmacy, University of Reading, Reading RG6 6UB, UK; (M.S.); (J.R.A.); (E.R.)
| | - José R. Almeida
- School of Pharmacy, University of Reading, Reading RG6 6UB, UK; (M.S.); (J.R.A.); (E.R.)
| | - Elanchezhian Rajan
- School of Pharmacy, University of Reading, Reading RG6 6UB, UK; (M.S.); (J.R.A.); (E.R.)
| | - Harry F. Williams
- Toxiven Biotech Private Limited, Coimbatore 641042, Tamil Nadu, India;
| | - Felix Townsend
- School of Biological Sciences, University of Reading, Reading RG6 6UB, UK; (F.T.); (E.C.); (K.P.)
| | - Elizabeth Cornish
- School of Biological Sciences, University of Reading, Reading RG6 6UB, UK; (F.T.); (E.C.); (K.P.)
| | | | - Ketan Patel
- School of Biological Sciences, University of Reading, Reading RG6 6UB, UK; (F.T.); (E.C.); (K.P.)
| | - Sakthivel Vaiyapuri
- School of Pharmacy, University of Reading, Reading RG6 6UB, UK; (M.S.); (J.R.A.); (E.R.)
| |
Collapse
|
2
|
Richards NJ, Alqallaf A, Mitchell RD, Parnell A, Haidar HB, Almeida JR, Williams J, Vijayakumar P, Balogun A, Matsakas A, Trim SA, Patel K, Vaiyapuri S. Indian Ornamental Tarantula ( Poecilotheria regalis) Venom Affects Myoblast Function and Causes Skeletal Muscle Damage. Cells 2023; 12:2074. [PMID: 37626884 PMCID: PMC10453882 DOI: 10.3390/cells12162074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2023] [Revised: 08/03/2023] [Accepted: 08/09/2023] [Indexed: 08/27/2023] Open
Abstract
Envenomation by the Indian ornamental tarantula (Poecilotheria regalis) is medically relevant to humans, both in its native India and worldwide, where they are kept as pets. Muscle-related symptoms such as cramps and pain are commonly reported in humans following envenomation by this species. There is no specific treatment, including antivenom, for its envenomation. Moreover, the scientific knowledge of the impact of this venom on skeletal muscle function is highly limited. Therefore, we carried out this study to better understand the myotoxic properties of Poecilotheria regalis venom by determining its effects in cultured myoblasts and in the tibialis anterior muscle in mice. While there was no effect found on undifferentiated myoblasts, the venom affected differentiated multinucleated myotubes resulting in the reduction of fusion and atrophy of myotubes. Similarly, intramuscular administration of this venom in the tibialis anterior muscle in mice resulted in extensive muscle damage on day 5. However, by day 10, the regeneration was evident, and the regeneration process continued until day 20. Nevertheless, some tissue abnormalities including reduced dystrophin expression and microthrombi presence were observed on day 20. Overall, this study demonstrates the ability of this venom to induce significant muscle damage and affect its regeneration in the early stages. These data provide novel mechanistic insights into this venom-induced muscle damage and guide future studies to isolate and characterise individual toxic component(s) that induce muscle damage and their significance in developing better therapeutics.
Collapse
Affiliation(s)
- Nicholas J. Richards
- School of Biological Sciences, University of Reading, Reading RG6 6UB, UK; (N.J.R.); (A.A.); (A.P.); (H.B.H.)
| | - Ali Alqallaf
- School of Biological Sciences, University of Reading, Reading RG6 6UB, UK; (N.J.R.); (A.A.); (A.P.); (H.B.H.)
- Medical Services Authority, Ministry of Defence, Kuwait City 13012, Kuwait
| | | | - Andrew Parnell
- School of Biological Sciences, University of Reading, Reading RG6 6UB, UK; (N.J.R.); (A.A.); (A.P.); (H.B.H.)
- Micregen Ltd., Thames Valley Science Park, Reading RG2 9LH, UK;
| | - Husain Bin Haidar
- School of Biological Sciences, University of Reading, Reading RG6 6UB, UK; (N.J.R.); (A.A.); (A.P.); (H.B.H.)
| | - José R. Almeida
- School of Pharmacy, University of Reading, Reading RG6 6UB, UK; (J.R.A.); (J.W.); (P.V.)
| | - Jarred Williams
- School of Pharmacy, University of Reading, Reading RG6 6UB, UK; (J.R.A.); (J.W.); (P.V.)
| | - Pradeep Vijayakumar
- School of Pharmacy, University of Reading, Reading RG6 6UB, UK; (J.R.A.); (J.W.); (P.V.)
| | - Adedoyin Balogun
- Molecular Physiology Laboratory, Centre for Biomedicine, Hull York Medical School, Hull HU6 7RX, UK
| | - Antonios Matsakas
- Molecular Physiology Laboratory, Centre for Biomedicine, Hull York Medical School, Hull HU6 7RX, UK
| | | | - Ketan Patel
- School of Biological Sciences, University of Reading, Reading RG6 6UB, UK; (N.J.R.); (A.A.); (A.P.); (H.B.H.)
| | - Sakthivel Vaiyapuri
- School of Pharmacy, University of Reading, Reading RG6 6UB, UK; (J.R.A.); (J.W.); (P.V.)
| |
Collapse
|
3
|
Tietjen M, Pérez de León AA, Sagel A, Skoda SR, Phillips PL, Mitchell RD, Caruth J, Durán U, Musai L, Tortosa S, Arp AP. Geographic Population Genetic Structure of the New World Screwworm, Cochliomyia hominivorax (Diptera: Calliphoridae), Using SNPs. J Med Entomol 2022; 59:874-882. [PMID: 35323976 DOI: 10.1093/jme/tjac024] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Indexed: 06/14/2023]
Abstract
The New World screwworm, Cochliomyia hominivorax (Coquerel 1858) (Diptera: Calliphoridae), is a serious parasite of livestock, humans, and other warm-blooded animals. It has been eradicated from the northern parts of its historical range down to the Panama-Colombian border where a permanent barrier zone is maintained. This eradication was accomplished through using the sterile insect technique (SIT). In 2016 there was an outbreak of C. hominivorax in the Florida Keys. In only six months, this pest was successfully re-eradicated using SIT, but the geographic origin of the invasion has yet to be resolved. It was previously determined that the Florida flies most likely represented a single invasion, and it was recommended that a finer-scale genetic assessment should be completed. Thus, this current proof-of-concept study aimed to develop a population genetic database using single nucleotide polymorphisms (SNPs) to reference outbreaks and potentially identify the origin of the Florida outbreak. This initial database consists of wild-caught samples from 4 geographic locations as well as laboratory colony samples that originated from 7 additional locations using a genotyping by sequencing (GBS) approach. Geographic population structuring was identified for twelve populations that clustered according to geographic location. The Florida outbreak samples appeared similar to samples from the outer Caribbean cluster which included samples from Dominican Republic and Trinidad and Tobago, however, these results will be further clarified with the replacement of laboratory colony samples with future wild-caught samples.
Collapse
Affiliation(s)
- Mackenzie Tietjen
- United States Department of Agriculture, Agricultural Research Service, Knipling-Bushland U.S. Livestock Insects Research Laboratory, 2700 Fredericksburg Road, Kerrville, TX, 78028, USA
| | - Adalberto A Pérez de León
- United States Department of Agriculture, Agricultural Research Service, San Joaquin Valley Agricultural Sciences Center: Parlier, CA, 93648, USA
| | - Agustin Sagel
- United States Department of Agriculture, Agricultural Research Service, Screwworm Research Unit, Pacora, Panama
| | - Steve R Skoda
- United States Department of Agriculture, Agricultural Research Service, Knipling-Bushland U.S. Livestock Insects Research Laboratory, 2700 Fredericksburg Road, Kerrville, TX, 78028, USA
| | - Pamela L Phillips
- United States Department of Agriculture, Animal and Plant Health Inspection Service, International Services, International Services, Pacora, Panama
| | - Robert D Mitchell
- U.S. Environmental Protection Agency, Office of Pesticide Programs, Washington, DC, 20460, USA
| | - Joanne Caruth
- Animal Health Unit, Division of Food Production Forestry and Fisheries, Tobago House of Assembly. Hope Farm, Trinidad and Tobago
| | - Uziel Durán
- Direccion General de Ganaderia (DIGEGA), Ministry of Agriculture of the Dominican Republic, Santo Domingo, Dominican Republic
| | - Lisa Musai
- Animal Production and Health Division, Ministry of Agriculture, Land and Fisheries, Port of Spain, Trinidad and Tobago
| | - Silvia Tortosa
- Direccion General de Ganaderia (DIGEGA), Ministry of Agriculture of the Dominican Republic, Santo Domingo, Dominican Republic
| | - Alex P Arp
- United States Department of Agriculture, Agricultural Research Service, Screwworm Research Unit, Pacora, Panama
| |
Collapse
|
4
|
Lawrie RD, Mitchell RD, Deguenon JM, Ponnusamy L, Reisig D, Pozo-Valdivia AD, Kurtz RW, Roe RM. Characterization of Long Non-Coding RNAs in the Bollworm, Helicoverpa zea, and Their Possible Role in Cry1Ac-Resistance. Insects 2021; 13:12. [PMID: 35055855 PMCID: PMC8779162 DOI: 10.3390/insects13010012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Revised: 12/19/2021] [Accepted: 12/20/2021] [Indexed: 12/13/2022]
Abstract
Multiple insect pest species have developed field resistance to Bt-transgenic crops. There has been a significant amount of research on protein-coding genes that contribute to resistance, such as the up-regulation of protease activity or altered receptors. However, our understanding of the role of non-protein-coding mechanisms in Bt-resistance is minimal, as is also the case for resistance to chemical pesticides. To address this problem relative to Bt, RNA-seq was used to examine statistically significant, differential gene expression between a Cry1Ac-resistant (~100-fold resistant) and Cry1Ac-susceptible strain of Helicoverpa zea, a prevalent caterpillar pest in the USA. Significant differential expression of putative long non-coding RNAs (lncRNAs) was found in the Cry1Ac-resistant strain (58 up- and 24 down-regulated gene transcripts with an additional 10 found only in resistant and four only in susceptible caterpillars). These lncRNAs were examined as potential pseudogenes and for their genomic proximity to coding genes, both of which can be indicative of regulatory relationships between a lncRNA and coding gene expression. A possible pseudogenic lncRNA was found with similarities to a cadherin. In addition, putative lncRNAs were found significantly proximal to a serine protease, ABC transporter, and CYP coding genes, potentially involved in the mechanism of Bt and/or chemical insecticide resistance. Characterization of non-coding genetic mechanisms in Helicoverpa zea will improve the understanding of the genomic evolution of insect resistance, improve the identification of specific regulators of coding genes in general (some of which could be important in resistance), and is the first step for potentially targeting these regulators for pest control and resistance management (using molecular approaches, such as RNAi and others).
Collapse
Affiliation(s)
- Roger D. Lawrie
- Department of Entomology and Plant Pathology, North Carolina State University, Campus Box 7647, 3230 Ligon Street, Raleigh, NC 27695, USA; (R.D.L.); (R.D.M.III); (J.M.D.); (L.P.)
- Environmental and Molecular Toxicology Program, Department of Biology, College of Sciences, North Carolina State University, 2601 Stinson Drive, Raleigh, NC 27606, USA
| | - Robert D. Mitchell
- Department of Entomology and Plant Pathology, North Carolina State University, Campus Box 7647, 3230 Ligon Street, Raleigh, NC 27695, USA; (R.D.L.); (R.D.M.III); (J.M.D.); (L.P.)
- Office of Pesticide Programs, Invertebrate and Vertebrate Branch 1, Registration Division, U.S. Environmental Protection Agency, 1200 Pennsylvania Avenue, Washington, DC 20460, USA
| | - Jean Marcel Deguenon
- Department of Entomology and Plant Pathology, North Carolina State University, Campus Box 7647, 3230 Ligon Street, Raleigh, NC 27695, USA; (R.D.L.); (R.D.M.III); (J.M.D.); (L.P.)
| | - Loganathan Ponnusamy
- Department of Entomology and Plant Pathology, North Carolina State University, Campus Box 7647, 3230 Ligon Street, Raleigh, NC 27695, USA; (R.D.L.); (R.D.M.III); (J.M.D.); (L.P.)
| | - Dominic Reisig
- Vernon G. James Research & Extension Center, Department of Entomology and Plant Pathology, 207 Research Station Road, Plymouth, NC 27962, USA; (D.R.); (A.D.P.-V.)
| | - Alejandro Del Pozo-Valdivia
- Vernon G. James Research & Extension Center, Department of Entomology and Plant Pathology, 207 Research Station Road, Plymouth, NC 27962, USA; (D.R.); (A.D.P.-V.)
| | - Ryan W. Kurtz
- Cotton Incorporated, 6399 Weston Parkway, Cary, NC 27513, USA;
| | - Richard Michael Roe
- Department of Entomology and Plant Pathology, North Carolina State University, Campus Box 7647, 3230 Ligon Street, Raleigh, NC 27695, USA; (R.D.L.); (R.D.M.III); (J.M.D.); (L.P.)
- Environmental and Molecular Toxicology Program, Department of Biology, College of Sciences, North Carolina State University, 2601 Stinson Drive, Raleigh, NC 27606, USA
| |
Collapse
|
5
|
Ahmad F, Mitchell RD, Houben T, Palo A, Yadati T, Parnell AJ, Patel K, Shiri-Sverdlov R, Leake DS. Cysteamine Decreases Low-Density Lipoprotein Oxidation, Causes Regression of Atherosclerosis, and Improves Liver and Muscle Function in Low-Density Lipoprotein Receptor-Deficient Mice. J Am Heart Assoc 2021; 10:e017524. [PMID: 34493066 PMCID: PMC8649511 DOI: 10.1161/jaha.120.017524] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Background We have shown previously that low‐density lipoprotein (LDL) can be oxidized in the lysosomes of macrophages, that this oxidation can be inhibited by cysteamine, an antioxidant that accumulates in lysosomes, and that this drug decreases atherosclerosis in LDL receptor–deficient mice fed a high‐fat diet. We have now performed a regression study with cysteamine, which is of more relevance to the treatment of human disease. Methods and Results LDL receptor–deficient mice were fed a high‐fat diet to induce atherosclerotic lesions. They were then reared on chow diet and drinking water containing cysteamine or plain drinking water. Aortic atherosclerosis was assessed, and samples of liver and skeletal muscle were analyzed. There was no regression of atherosclerosis in the control mice, but cysteamine caused regression of between 32% and 56% compared with the control group, depending on the site of the lesions. Cysteamine substantially increased markers of lesion stability, decreased ceroid, and greatly decreased oxidized phospholipids in the lesions. The liver lipid levels and expression of cluster of differentiation 68, acetyl–coenzyme A acetyltransferase 2, cytochromes P450 (CYP)27, and proinflammatory cytokines and chemokines were decreased by cysteamine. Skeletal muscle function and oxidative fibers were increased by cysteamine. There were no changes in the plasma total cholesterol, LDL cholesterol, high‐density lipoprotein cholesterol, or triacylglycerol concentrations attributable to cysteamine. Conclusions Inhibiting the lysosomal oxidation of LDL in atherosclerotic lesions by antioxidants targeted at lysosomes causes the regression of atherosclerosis and improves liver and muscle characteristics in mice and might be a promising novel therapy for atherosclerosis in patients.
Collapse
Affiliation(s)
- Feroz Ahmad
- School of Biological Sciences University of Reading Reading UK
| | | | - Tom Houben
- Department of Molecular Genetics Maastricht University Maastricht the Netherlands
| | - Angela Palo
- Department of Molecular Genetics Maastricht University Maastricht the Netherlands
| | - Tulasi Yadati
- Department of Molecular Genetics Maastricht University Maastricht the Netherlands
| | | | - Ketan Patel
- School of Biological Sciences University of Reading Reading UK
| | - Ronit Shiri-Sverdlov
- Department of Molecular Genetics Maastricht University Maastricht the Netherlands
| | - David S Leake
- School of Biological Sciences University of Reading Reading UK
| |
Collapse
|
6
|
Luan K, West AJ, McCord MG, DenHartog EA, Shi Q, Bettermann I, Li J, Travanty NV, Mitchell RD, Cave GL, Strider JB, Wang Y, Neumann F, Beck T, Apperson CS, Roe RM. Mosquito-Textile Physics: A Mathematical Roadmap to Insecticide-Free, Bite-Proof Clothing for Everyday Life. Insects 2021; 12:insects12070636. [PMID: 34357296 PMCID: PMC8306269 DOI: 10.3390/insects12070636] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Revised: 07/07/2021] [Accepted: 07/09/2021] [Indexed: 11/23/2022]
Abstract
Simple Summary Mosquitoes can bite across clothing and transmit disease. This is prevented with pesticides applied to clothing. We developed non-insecticidal cloth and garments that provided 100% protection, were comfortable and look-like and feel-like regular clothing. Abstract Garments treated with chemical insecticides are commonly used to prevent mosquito bites. Resistance to insecticides, however, is threatening the efficacy of this technology, and people are increasingly concerned about the potential health impacts of wearing insecticide-treated clothing. Here, we report a mathematical model for fabric barriers that resist bites from Aedes aegypti mosquitoes based on textile physical structure and no insecticides. The model was derived from mosquito morphometrics and analysis of mosquito biting behavior. Woven filter fabrics, precision polypropylene plates, and knitted fabrics were used for model validation. Then, based on the model predictions, prototype knitted textiles and garments were developed that prevented mosquito biting, and comfort testing showed the garments to possess superior thermophysiological properties. Our fabrics provided a three-times greater bite resistance than the insecticide-treated cloth. Our predictive model can be used to develop additional textiles in the future for garments that are highly bite resistant to mosquitoes.
Collapse
Affiliation(s)
- Kun Luan
- Department of Forest Biomaterials, College of Natural Resources, NC State University, Raleigh, NC 27695, USA; (K.L.); (M.G.M.)
- Department of Textile Engineering, Chemistry and Science, Wilson College of Textiles, NC State University, Raleigh, NC 27695, USA; (E.A.D.); (Q.S.); (Y.W.)
| | - Andre J. West
- Department of Textile and Apparel, Technology and Management, Wilson College of Textiles, NC State University, Raleigh, NC 27695, USA;
- Correspondence: (A.J.W.); (R.M.R.)
| | - Marian G. McCord
- Department of Forest Biomaterials, College of Natural Resources, NC State University, Raleigh, NC 27695, USA; (K.L.); (M.G.M.)
| | - Emiel A. DenHartog
- Department of Textile Engineering, Chemistry and Science, Wilson College of Textiles, NC State University, Raleigh, NC 27695, USA; (E.A.D.); (Q.S.); (Y.W.)
| | - Quan Shi
- Department of Textile Engineering, Chemistry and Science, Wilson College of Textiles, NC State University, Raleigh, NC 27695, USA; (E.A.D.); (Q.S.); (Y.W.)
| | - Isa Bettermann
- Institut für Textiltechnik der RWTH, Aachen University, 52062 Aachen, Germany; (I.B.); (F.N.); (T.B.)
| | - Jiayin Li
- Department of Textile and Apparel, Technology and Management, Wilson College of Textiles, NC State University, Raleigh, NC 27695, USA;
| | - Nicholas V. Travanty
- Department of Entomology & Plant Pathology, College of Agriculture and Life Sciences, NC State University, Raleigh, NC 27695, USA; (N.V.T.); (R.D.M.III); (G.L.C.); (J.B.S.); (C.S.A.)
| | - Robert D. Mitchell
- Department of Entomology & Plant Pathology, College of Agriculture and Life Sciences, NC State University, Raleigh, NC 27695, USA; (N.V.T.); (R.D.M.III); (G.L.C.); (J.B.S.); (C.S.A.)
| | - Grayson L. Cave
- Department of Entomology & Plant Pathology, College of Agriculture and Life Sciences, NC State University, Raleigh, NC 27695, USA; (N.V.T.); (R.D.M.III); (G.L.C.); (J.B.S.); (C.S.A.)
| | - John B. Strider
- Department of Entomology & Plant Pathology, College of Agriculture and Life Sciences, NC State University, Raleigh, NC 27695, USA; (N.V.T.); (R.D.M.III); (G.L.C.); (J.B.S.); (C.S.A.)
| | - Yongxin Wang
- Department of Textile Engineering, Chemistry and Science, Wilson College of Textiles, NC State University, Raleigh, NC 27695, USA; (E.A.D.); (Q.S.); (Y.W.)
| | - Florian Neumann
- Institut für Textiltechnik der RWTH, Aachen University, 52062 Aachen, Germany; (I.B.); (F.N.); (T.B.)
| | - Tobias Beck
- Institut für Textiltechnik der RWTH, Aachen University, 52062 Aachen, Germany; (I.B.); (F.N.); (T.B.)
| | - Charles S. Apperson
- Department of Entomology & Plant Pathology, College of Agriculture and Life Sciences, NC State University, Raleigh, NC 27695, USA; (N.V.T.); (R.D.M.III); (G.L.C.); (J.B.S.); (C.S.A.)
- Comparative Medicine Institute, NC State University, Raleigh, NC 27695, USA
| | - R. Michael Roe
- Department of Entomology & Plant Pathology, College of Agriculture and Life Sciences, NC State University, Raleigh, NC 27695, USA; (N.V.T.); (R.D.M.III); (G.L.C.); (J.B.S.); (C.S.A.)
- Comparative Medicine Institute, NC State University, Raleigh, NC 27695, USA
- Correspondence: (A.J.W.); (R.M.R.)
| |
Collapse
|
7
|
Ponnusamy L, Sutton H, Mitchell RD, Sonenshine DE, Apperson CS, Roe RM. Tick Ecdysteroid Hormone, Global Microbiota/ Rickettsia Signaling in the Ovary versus Carcass during Vitellogenesis in Part-Fed (Virgin) American Dog Ticks, Dermacentor variabilis. Microorganisms 2021; 9:1242. [PMID: 34201013 PMCID: PMC8228290 DOI: 10.3390/microorganisms9061242] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Revised: 06/02/2021] [Accepted: 06/05/2021] [Indexed: 02/01/2023] Open
Abstract
The transovarial transmission of tick-borne bacterial pathogens is an important mechanism for their maintenance in natural populations and transmission, causing disease in humans and animals. The mechanism for this transmission and the possible role of tick hormones facilitating this process have never been studied. Injections of physiological levels of the tick hormone, 20-hydroxyecdysone (20E), into part-fed (virgin) adult females of the American dog tick, Dermacentor variabilis, attached to the host caused a reduction in density of Rickettsia montanensis in the carcass and an increase in the ovaries compared to buffer-injected controls. This injection initiates yolk protein synthesis and uptake by the eggs but has no effect on blood feeding. Francisella sp. and R. montanensis were the predominant bacteria based on the proportionality in the carcass and ovary. The total bacteria load increased in the carcass and ovaries, and bacteria in the genus Pseudomonas increased in the carcass after the 20E injection. The mechanism of how the Rickettsia species respond to changes in tick hormonal regulation needs further investigation. Multiple possible mechanisms for the proliferation of R. montanensis in the ovaries are proposed.
Collapse
Affiliation(s)
- Loganathan Ponnusamy
- Department of Entomology and Plath Pathology, North Carolina State University, Raleigh, NC 27695, USA; (L.P.); (H.S.); (R.D.M.III); (C.S.A.)
- Comparative Medicine Institute, North Carolina State University, Raleigh, NC 27695, USA
| | - Haley Sutton
- Department of Entomology and Plath Pathology, North Carolina State University, Raleigh, NC 27695, USA; (L.P.); (H.S.); (R.D.M.III); (C.S.A.)
- North Carolina Department of Agriculture and Consumer Services, Raleigh, NC 27601, USA
| | - Robert D. Mitchell
- Department of Entomology and Plath Pathology, North Carolina State University, Raleigh, NC 27695, USA; (L.P.); (H.S.); (R.D.M.III); (C.S.A.)
- Office of Pesticide Programs, Invertebrate and Vertebrate Branch 1, Registration Division, U.S. Environmental Protection Agency, 1200 Pennsylvania Ave., Washington, DC 20460, USA
| | - Daniel E. Sonenshine
- Department of Biological Sciences, Old Dominion University, Norfolk, VA 23529, USA;
| | - Charles S. Apperson
- Department of Entomology and Plath Pathology, North Carolina State University, Raleigh, NC 27695, USA; (L.P.); (H.S.); (R.D.M.III); (C.S.A.)
- Comparative Medicine Institute, North Carolina State University, Raleigh, NC 27695, USA
| | - Richard Michael Roe
- Department of Entomology and Plath Pathology, North Carolina State University, Raleigh, NC 27695, USA; (L.P.); (H.S.); (R.D.M.III); (C.S.A.)
- Comparative Medicine Institute, North Carolina State University, Raleigh, NC 27695, USA
| |
Collapse
|
8
|
O'Reilly GM, Mitchell RD, Mitra B, Akhlaghi H, Tran V, Furyk JS, Buntine P, Wong A, Gangathimmaiah V, Knott J, Raos M, Chatterton E, Sevior C, Parker S, Baker S, Loughman A, Lowry N, Freeman D, Sri-Ganeshan M, Chapman N, Siu S, Noonan MP, Smit DV, Cameron PA. Epidemiology and clinical features of emergency department patients with suspected COVID-19: Insights from Australia's 'second wave' (COVED-4). Emerg Med Australas 2021; 33:331-342. [PMID: 33315310 DOI: 10.1111/1742-6723.13706] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Accepted: 12/08/2020] [Indexed: 12/13/2022]
Abstract
OBJECTIVE The aim of the present study was to describe the epidemiology and clinical features of patients presenting to the ED with suspected and confirmed COVID-19 during Australia's 'second wave'. METHODS The COVID-19 ED (COVED) Project is an ongoing prospective cohort study in Australian EDs. This analysis presents data from 12 sites across four Australian states for the period from 1 July to 31 August 2020. All adult patients who met the criteria for 'suspected COVID-19' and underwent testing for SARS-CoV-2 in the ED were eligible for inclusion. Study outcomes included a positive SARS-CoV-2 test result, mechanical ventilation and in-hospital mortality. RESULTS There were 106 136 presentations to the participating EDs and 12 055 (11.4%; 95% confidence interval [CI] 11.2-11.6) underwent testing for SARS-CoV-2. Of these, 255 (2%) patients returned a positive result. Among positive cases, 13 (5%) received mechanical ventilation during their hospital admission compared to 122 (2%) of the SARS-CoV-2 negative patients (odds ratio 2.7; 95% CI 1.5-4.9, P = 0.001). Nineteen (7%) SARS-CoV-2 positive patients died in hospital compared to 212 (3%) of the SARS-CoV-2 negative patients (odds ratio 2.3; 95% CI 1.4-3.7, P = 0.001). Strong clinical predictors of the SARS-CoV-2 test result included self-reported fever, sore throat, bilateral infiltrates on chest X-ray, and absence of a leucocytosis on first ED blood tests (P < 0.05). CONCLUSIONS In this prospective multi-site study during Australia's 'second wave', a substantial proportion of ED presentations required SARS-CoV-2 testing and isolation. Presence of SARS-CoV-2 on nasopharyngeal swab was associated with an increase in the odds of death and mechanical ventilation in hospital.
Collapse
Affiliation(s)
- Gerard M O'Reilly
- Emergency and Trauma Centre, Alfred Health, Melbourne, Victoria, Australia.,School of Public Health and Preventive Medicine, Monash University, Melbourne, Victoria, Australia.,National Trauma Research Institute, Alfred Health, Melbourne, Victoria, Australia
| | - Robert D Mitchell
- Emergency and Trauma Centre, Alfred Health, Melbourne, Victoria, Australia.,School of Public Health and Preventive Medicine, Monash University, Melbourne, Victoria, Australia
| | - Biswadev Mitra
- Emergency and Trauma Centre, Alfred Health, Melbourne, Victoria, Australia.,School of Public Health and Preventive Medicine, Monash University, Melbourne, Victoria, Australia.,National Trauma Research Institute, Alfred Health, Melbourne, Victoria, Australia
| | - Hamed Akhlaghi
- Emergency Department, St Vincent's Hospital, Melbourne, Victoria, Australia.,Melbourne Medical School, The University of Melbourne, Melbourne, Victoria, Australia
| | - Viet Tran
- Emergency Department, Royal Hobart Hospital, Hobart, Tasmania, Australia.,Tasmanian School of Medicine, University of Tasmania, Hobart, Tasmania, Australia.,Menzies Institute for Medical Research, University of Tasmania, Hobart, Tasmania, Australia
| | - Jeremy S Furyk
- Emergency Department, Barwon Health, Geelong, Victoria, Australia.,School of Medicine, Deakin University, Geelong, Victoria, Australia
| | - Paul Buntine
- Emergency Department, Eastern Health, Melbourne, Victoria, Australia.,Eastern Health Clinical School, Monash University, Melbourne, Victoria, Australia
| | - Anselm Wong
- Emergency Department, Austin Hospital, Melbourne, Victoria, Australia.,Department of Critical Care, The University of Melbourne, Melbourne, Victoria, Australia.,School of Clinical Sciences, Monash University, Melbourne, Victoria, Australia
| | - Vinay Gangathimmaiah
- Emergency Department, Townsville University Hospital, Townsville, Queensland, Australia
| | - Jonathan Knott
- Department of Critical Care, The University of Melbourne, Melbourne, Victoria, Australia.,Emergency Department, The Royal Melbourne Hospital, Melbourne, Victoria, Australia
| | - Max Raos
- Emergency Department, Sutherland Hospital, Sydney, New South Wales, Australia
| | - Erica Chatterton
- Emergency and Trauma Centre, Alfred Health, Melbourne, Victoria, Australia.,School of Nursing and Midwifery, La Trobe University, Melbourne, Victoria, Australia.,School of Nursing and Midwifery, Deakin University, Melbourne, Victoria, Australia
| | - Carolyne Sevior
- Emergency and Trauma Centre, Alfred Health, Melbourne, Victoria, Australia
| | - Sophie Parker
- Emergency and Trauma Centre, Alfred Health, Melbourne, Victoria, Australia.,Department of Anaesthetics, Peter MacCallum Hospital, Melbourne, Victoria, Australia
| | - Samuel Baker
- Emergency Department, St Vincent's Hospital, Melbourne, Victoria, Australia
| | - Ashley Loughman
- Emergency Department, Royal Hobart Hospital, Hobart, Tasmania, Australia.,Ambulance Tasmania, Hobart, Tasmania, Australia
| | - Nicole Lowry
- Emergency Department, Barwon Health, Geelong, Victoria, Australia
| | - Dylan Freeman
- Emergency Department, Eastern Health, Melbourne, Victoria, Australia
| | | | - Nicole Chapman
- Emergency Department, Townsville University Hospital, Townsville, Queensland, Australia
| | - Sherman Siu
- Emergency Department, Sutherland Hospital, Sydney, New South Wales, Australia
| | - Michael P Noonan
- Emergency and Trauma Centre, Alfred Health, Melbourne, Victoria, Australia.,National Trauma Research Institute, Alfred Health, Melbourne, Victoria, Australia.,Trauma Service, Alfred Health, Melbourne, Victoria, Australia
| | - De Villiers Smit
- Emergency and Trauma Centre, Alfred Health, Melbourne, Victoria, Australia.,School of Public Health and Preventive Medicine, Monash University, Melbourne, Victoria, Australia.,National Trauma Research Institute, Alfred Health, Melbourne, Victoria, Australia
| | - Peter A Cameron
- Emergency and Trauma Centre, Alfred Health, Melbourne, Victoria, Australia.,School of Public Health and Preventive Medicine, Monash University, Melbourne, Victoria, Australia
| | | |
Collapse
|
9
|
Armstrong BA, Kneubehl AR, Mitchell RD, Krishnavajhala A, Teel PD, Pérez de León AA, Lopez JE. Corrigendum: Differential Expression of Putative Ornithodoros turicata Defensins Mediated by Tick Feeding. Front Cell Infect Microbiol 2020; 10:310. [PMID: 32714879 PMCID: PMC7345982 DOI: 10.3389/fcimb.2020.00310] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Accepted: 05/22/2020] [Indexed: 11/17/2022] Open
Affiliation(s)
- Brittany A Armstrong
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX, United States.,Department of Pediatrics, National School of Tropical Medicine, Baylor College of Medicine, Houston, TX, United States
| | - Alexander R Kneubehl
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX, United States.,Department of Pediatrics, National School of Tropical Medicine, Baylor College of Medicine, Houston, TX, United States
| | - Robert D Mitchell
- Knipling-Bushland U.S. Livestock Insects Research Laboratory, Veterinary Pest Genomics Center, Department of Agriculture-Agricultural Research Service, Kerrville, TX, United States
| | - Aparna Krishnavajhala
- Department of Pediatrics, National School of Tropical Medicine, Baylor College of Medicine, Houston, TX, United States
| | - Pete D Teel
- Department of Entomology, Texas A&M AgriLife Research, College Station, TX, United States
| | - Adalberto A Pérez de León
- Knipling-Bushland U.S. Livestock Insects Research Laboratory, Veterinary Pest Genomics Center, Department of Agriculture-Agricultural Research Service, Kerrville, TX, United States
| | - Job E Lopez
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX, United States.,Department of Pediatrics, National School of Tropical Medicine, Baylor College of Medicine, Houston, TX, United States
| |
Collapse
|
10
|
Lawrie RD, Mitchell RD, Dhammi A, Wallace A, Hodgson E, Roe RM. Role of long non-coding RNA in DEET- and fipronil-mediated alteration of transcripts associated with Phase I and Phase II xenobiotic metabolism in human primary hepatocytes. Pestic Biochem Physiol 2020; 167:104607. [PMID: 32527422 DOI: 10.1016/j.pestbp.2020.104607] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2019] [Revised: 05/07/2020] [Accepted: 05/15/2020] [Indexed: 06/11/2023]
Abstract
Human exposure to environmental chemicals both individually and in combination occurs frequently world-wide most often with unknown consequences. Use of molecular approaches to aide in the assessment of risk involved in chemical exposure is a growing field in toxicology. In this study, we examined the impact of two environmental chemicals used in and around homes, the insect repellent DEET (N,N-diethyl-m-toluamide) and the phenylpyrazole insecticide fipronil (fluocyanobenpyrazole) on transcript levels of enzymes potentially involved in xenobiotic metabolism and on long non-coding RNAs (lncRNAs). Primary human hepatocytes were treated with these two chemicals both individually and in combination. Using RNA-Seq, we found that 10 major enzyme categories involved in phase 1 and phase 2 xenobiotic metabolism were significantly (α = 0.05) up- and down-regulated (i.e., 100 μM DEET-19 transcripts, 89% up and 11% down; 10 μM fipronil-52 transcripts, 53% up and 47% down; and 100 μM DEET +10 μM fipronil-69 transcripts, 43% up and 57% down). The altered genes were then mapped to the human genome and their proximity (within 1,000,000 bp) to lncRNAs examined. Unique proximities were discovered between altered lncRNA and altered P450s (CYP) and other enzymes (DEET, 2 CYP; Fipronil, 6 CYP and 15 other; and DEET + fipronil, 7 CYP and 21 other). Many of the altered P450 transcripts were in multiple clusters in the genome with proximal altered lncRNAs, suggesting a regulator function for the lncRNA. At the gene level there was high percent identity for lncRNAs near P450 clusters, but this relationship was not found at the transcript level. The role of these altered lncRNAs associated with xenobiotic induction, human diseases and chemical mixtures is discussed.
Collapse
Affiliation(s)
- Roger D Lawrie
- Toxicology Program, Department of Biology, North Carolina State University, Raleigh, NC 27695, USA; Department of Entomology and Plant Pathology, North Carolina State University, Raleigh, NC 27695, USA
| | - Robert D Mitchell
- Toxicology Program, Department of Biology, North Carolina State University, Raleigh, NC 27695, USA; United States Department of Agriculture, Agricultural Research Service, U.S. Livestock Insects Research Lab, Kerrville, TX 78028, USA
| | - Anirudh Dhammi
- Department of Entomology and Plant Pathology, North Carolina State University, Raleigh, NC 27695, USA
| | - Andrew Wallace
- Toxicology Program, Department of Biology, North Carolina State University, Raleigh, NC 27695, USA
| | - Ernest Hodgson
- Department of Applied Ecology, North Carolina State University, Raleigh, NC 27695, USA
| | - R Michael Roe
- Toxicology Program, Department of Biology, North Carolina State University, Raleigh, NC 27695, USA; Department of Entomology and Plant Pathology, North Carolina State University, Raleigh, NC 27695, USA.
| |
Collapse
|
11
|
Armstrong BA, Kneubehl AR, Mitchell RD, Krishnavajhala A, Teel PD, Pérez de León AA, Lopez JE. Differential Expression of Putative Ornithodoros turicata Defensins Mediated by Tick Feeding. Front Cell Infect Microbiol 2020; 10:152. [PMID: 32477960 PMCID: PMC7232577 DOI: 10.3389/fcimb.2020.00152] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Accepted: 03/23/2020] [Indexed: 11/13/2022] Open
Abstract
Additional research on soft ticks in the family Argasidae is needed to bridge the knowledge gap relative to hard ticks of the family Ixodidae; especially, the molecular mechanisms of Ornithodoros biology. Ornithodoros species are vectors of human and animal pathogens that include tick-borne relapsing fever spirochetes and African swine fever virus. Soft tick vector-pathogen interactions involving components of the tick immune response are not understood. Ticks utilize a basic innate immune system consisting of recognition factors and cellular and humoral responses to produce antimicrobial peptides, like defensins. In the present study, we identified and characterized the first putative defensins of Ornithodoros turicata, an argasid tick found primarily in the southwestern United States and regions of Latin America. Four genes (otdA, otdB, otdC, and otdD) were identified through sequencing and their predicted amino acid sequences contained motifs characteristic of arthropod defensins. A phylogenetic analysis grouped these four genes with arthropod defensins, and computational structural analyses further supported the identification. Since pathogens transmitted by O. turicata colonize both the midgut and salivary glands, expression patterns of the putative defensins were determined in these tissues 1 week post engorgement and after molting. Defensin genes up-regulated in the tick midgut 1 week post blood feeding were otdA and otdC, while otdD was up-regulated in the midgut of post-molt ticks. Moreover, otdB and otdD were also up-regulated in the salivary glands of flat post-molt ticks, while otdC was up-regulated within 1 week post blood-feeding. This work is foundational toward additional studies to determine mechanisms of vector competence and pathogen transmission from O. turicata.
Collapse
Affiliation(s)
- Brittany A Armstrong
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX, United States
- Department of Pediatrics, National School of Tropical Medicine, Baylor College of Medicine, Houston, TX, United States
| | - Alexander R Kneubehl
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX, United States
- Department of Pediatrics, National School of Tropical Medicine, Baylor College of Medicine, Houston, TX, United States
| | - Robert D Mitchell
- Knipling-Bushland U.S. Livestock Insects Research Laboratory, Veterinary Pest Genomics Center, Department of Agriculture-Agricultural Research Service, Kerrville, TX, United States
| | - Aparna Krishnavajhala
- Department of Pediatrics, National School of Tropical Medicine, Baylor College of Medicine, Houston, TX, United States
| | - Pete D Teel
- Department of Entomology, Texas A&M AgriLife Research, College Station, TX, United States
| | - Adalberto A Pérez de León
- Knipling-Bushland U.S. Livestock Insects Research Laboratory, Veterinary Pest Genomics Center, Department of Agriculture-Agricultural Research Service, Kerrville, TX, United States
| | - Job E Lopez
- Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX, United States
- Department of Pediatrics, National School of Tropical Medicine, Baylor College of Medicine, Houston, TX, United States
| |
Collapse
|
12
|
Abstract
Diverse groups of ectoparasitic arthropods cause significant morbidity and mortality in most of the approximately 1.49 billion head of cattle worldwide. Hematophagous ectoparasites (ie, blood-feeding flies, myiasis-causing flies, lice, mites, ticks) are the most important in cattle. Intense use of ectoparasiticides to treat infestations can result in ectoparasite populations becoming resistant to this treatment method. Approaches integrating the use of different technologies are required to manage cattle ectoparasites effectively while addressing societal expectations regarding food safety and environmental health. Assessing the status of coparasitism with ectoparasites and endoparasites in cattle across agroecosystems is critical in advancing integrated parasite management.
Collapse
Affiliation(s)
- Adalberto A Pérez de León
- United States Department of Agriculture - Agricultural Research Service, Knipling-Bushland U.S. Livestock Insects Research Laboratory and Veterinary Pest Genomics Center, 2700 Fredericksburg Road, Kerrville, TX 78028, USA.
| | - Robert D Mitchell
- United States Department of Agriculture - Agricultural Research Service, Knipling-Bushland U.S. Livestock Insects Research Laboratory and Veterinary Pest Genomics Center, 2700 Fredericksburg Road, Kerrville, TX 78028, USA
| | - David W Watson
- Entomology and Plant Pathology Department, North Carolina State University, Campus Box 7616, 1575 Varsity Drive, Raleigh, NC 27695-7616, USA
| |
Collapse
|
13
|
Khan A, Nasreen N, Niaz S, Ayaz S, Naeem H, Muhammad I, Said F, Mitchell RD, de León AAP, Gupta S, Kumar S. Acaricidal efficacy of Calotropis procera (Asclepiadaceae) and Taraxacum officinale (Asteraceae) against Rhipicephalus microplus from Mardan, Pakistan. Exp Appl Acarol 2019; 78:595-608. [PMID: 31367977 DOI: 10.1007/s10493-019-00406-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Accepted: 07/23/2019] [Indexed: 05/07/2023]
Abstract
Medicinal plants are used by traditional folk healers, modern physicians, and veterinarians as an alternative to conventional drugs to treat a wide range of disorders including parasitic diseases. Some compounds from these plants have been shown to have acaricidal activity and repel arthropods. The cattle tick Rhipicephalus microplus is one of the most destructive pests to the livestock industry in tropical and subtropical parts of the world. The potential to develop herbal acaricides to control R. microplus infestations is critical in maintaining cattle herd productivity, reducing economic losses, and curtailing the overuse of synthetic chemical acaricides. Calotropis procera, the apple of Sodom, and Taraxacum officinale, the common dandelion, were evaluated for acaricidal activity against R. microplus larvae and adults in vitro. Both plant species tested are common indigenous species of Pakistan where R. microplus infestations are widespread across livestock species including cattle, sheep, and goats. Whole-plant extracts derived from C. procera and T. officinale significantly reduced the index of egg laying (P < 0.01) and increased the percent inhibition of oviposition of adult female ticks at a concentration of 40 mg/mL when assessed by the adult immersion test (AIT). Calotropis procera and T. officinale treatments at the same concentration also resulted in larval mortality of 96.0% ± 0.57 and 96.7% ± 0.88, respectively, as measured using the larval packet test (LPT). An increasing range of extract concentrations was tested to determine the LD50 and LD90 for C. procera, 3.21 and 21.15 mg/mL, respectively, and T. officinale, 4.04 and 18.92 mg/mL, respectively. These results indicate that further studies are warranted to determine the relative contribution of individual phytochemicals from whole-plant extracts on acaricidal activity. This information will guide the design of further acaricidal efficacy tests using livestock infested with R. microplus.
Collapse
Affiliation(s)
- Adil Khan
- Department of Zoology, Abdul Wali Khan University, Mardan, 2320, Pakistan.
| | - Nasreen Nasreen
- Department of Zoology, Abdul Wali Khan University, Mardan, 2320, Pakistan
| | - Sadaf Niaz
- Department of Zoology, Abdul Wali Khan University, Mardan, 2320, Pakistan
| | - Sultan Ayaz
- College of Veterinary and Animal Husbandry, Abdul Wali Khan University, Mardan, Pakistan
| | - Huma Naeem
- Department of Parasitology, University of Veterinary and Animal Sciences, Lahore, 54600, Pakistan
| | - Ijaz Muhammad
- Department of Zoology, Abdul Wali Khan University, Mardan, 2320, Pakistan
| | - Fazal Said
- Department of Agriculture, Abdul Wali Khan University, Mardan, Pakistan
| | - Robert D Mitchell
- USDA-ARS, Knipling-Bushland U.S. Livestock Insects Research Laboratory and Veterinary Pest Genomics Center, Kerrville, TX, 78028, USA
| | - Adalberto A Pérez de León
- USDA-ARS, Knipling-Bushland U.S. Livestock Insects Research Laboratory and Veterinary Pest Genomics Center, Kerrville, TX, 78028, USA
| | - Snehil Gupta
- Department of Veterinary Parasitology, LUVAS, Hisar, Haryana, 125004, India
| | - Sachin Kumar
- Entomology Laboratory, Division of Parasitology, ICAR-Indian Veterinary Research Institute, Izatnagar, UP, 243122, India
| |
Collapse
|
14
|
Mitchell RD, Sonenshine DE, Pérez de León AA. Vitellogenin Receptor as a Target for Tick Control: A Mini-Review. Front Physiol 2019; 10:618. [PMID: 31178755 PMCID: PMC6537121 DOI: 10.3389/fphys.2019.00618] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Accepted: 05/02/2019] [Indexed: 12/20/2022] Open
Abstract
While much effort has been put into understanding vitellogenesis in insects and other organisms, much less is known of this process in ticks. There are several steps that facilitate yolk formation in developing oocytes of which the vitellogenin receptor (VgR) is a key component. The tick VgR binds vitellogenin (Vg) circulating in the hemolymph to initiate receptor-mediated endocytosis and its transformation into vitellin (Vn). The conversion of Vg into Vn, the final form of the yolk protein, occurs inside oocytes of the female tick ovary. Vn is critical to tick embryos since it serves as the nutritional source for their development, survival, and reproduction. Recent studies also suggest that pathogenic microbes, i.e., Babesia spp., that rely on ticks for propagation and dissemination likely "hitchhike" onto Vg molecules as they enter developing oocytes through the VgR. Suppressing VgR messenger RNA synthesis via RNA interference (RNAi) completely blocked Babesia spp. transmission into developing tick oocytes, thereby inhibiting vertical transmission of these pathogenic microbes from female to eggs. To date, VgRs from only four tick species, Dermacentor variabilis, Rhipicephalus microplus, Amblyomma hebraeum, and Haemaphysalis longicornis, have been fully sequenced and characterized. In contrast, many more VgRs have been described in various insect species. VgR is a critical component in egg formation and maturation that can serve as a precise target for tick control. However, additional research will help identify unique residues within the receptor that are specific to ticks or other arthropod disease vectors while avoiding cross-reactivity with non-target species. Detailed knowledge of the molecular structure and functional role of tick VgRs will enable development of novel vaccines to control ticks and tick-borne diseases.
Collapse
Affiliation(s)
- Robert D Mitchell
- USDA-ARS, Knipling-Bushland U.S. Livestock Insects Research Laboratory, Veterinary Pest Genomics Center, Kerrville, TX, United States
| | - Daniel E Sonenshine
- Laboratory for Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, United States.,Department of Biological Sciences, Old Dominion University, Norfolk, VA, United States
| | - Adalberto A Pérez de León
- USDA-ARS, Knipling-Bushland U.S. Livestock Insects Research Laboratory, Veterinary Pest Genomics Center, Kerrville, TX, United States
| |
Collapse
|
15
|
Mitchell RD, Zhu J, Carr AL, Dhammi A, Cave G, Sonenshine DE, Roe RM. Infrared light detection by the haller's organ of adult american dog ticks, Dermacentor variabilis (Ixodida: Ixodidae). Ticks Tick Borne Dis 2017. [PMID: 28647127 DOI: 10.1016/j.ttbdis.2017.06.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The Haller's organ (HO), unique to ticks and mites, is found only on the first tarsus of the front pair of legs. The organ has an unusual morphology consisting of an anterior pit (AP) with protruding sensilla and a posterior capsule (Cp). The current thinking is that the HO's main function is chemosensation analogous to the insect antennae, but the functionality of its atypical structure (exclusive to the Acari) is unexplained. We provide the first evidence that the HO allows the American dog tick, Dermacentor variabilis, to respond to infrared (IR) light. Unfed D. variabilis adults with their HOs present were positively phototactic to IR. However, when the HOs were removed, no IR response was detected. Ticks in these experiments were also attracted to white light with and without the HOs, but were only positively phototactic to white light when the ocelli (primitive eyes) were unobstructed. Covering the eyes did not prevent IR attraction. A putative TRPA1 receptor was characterized from a D. variabilis-specific HO transcriptome we constructed. This receptor was homologous to transient receptor potential cation channel, subfamily A, member 1 (TRPA1) from the pit organ of the pit viper, python, and boa families of snakes, the only receptor identified so far for IR detection. HO scanning electron microscopy (SEM) studies in the American dog tick showed the AP and Cp but also novel structures not previously described; the potential role of these structures in IR detection is discussed. The ability of ticks to use IR for host finding is consistent with their obligatory hematophagy and has practical applications in tick trapping and the development of new repellents.
Collapse
Affiliation(s)
- Robert D Mitchell
- Department of Entomology and Plant Pathology, Campus Box 7647, 3230 Ligon Street, North Carolina State University, Raleigh, NC, 27695-7647, USA.
| | - Jiwei Zhu
- Department of Entomology and Plant Pathology, Campus Box 7647, 3230 Ligon Street, North Carolina State University, Raleigh, NC, 27695-7647, USA.
| | - Ann L Carr
- Department of Entomology and Plant Pathology, Campus Box 7647, 3230 Ligon Street, North Carolina State University, Raleigh, NC, 27695-7647, USA.
| | - Anirudh Dhammi
- Department of Entomology and Plant Pathology, Campus Box 7647, 3230 Ligon Street, North Carolina State University, Raleigh, NC, 27695-7647, USA.
| | - Grayson Cave
- Department of Entomology and Plant Pathology, Campus Box 7647, 3230 Ligon Street, North Carolina State University, Raleigh, NC, 27695-7647, USA.
| | - Daniel E Sonenshine
- Department of Biological Sciences, Old Dominion University, Norfolk, VA, 23529, USA.
| | - R Michael Roe
- Department of Entomology and Plant Pathology, Campus Box 7647, 3230 Ligon Street, North Carolina State University, Raleigh, NC, 27695-7647, USA.
| |
Collapse
|
16
|
Mitchell RD, Dhammi A, Wallace A, Hodgson E, Roe RM. Impact of Environmental Chemicals on the Transcriptome of Primary Human Hepatocytes: Potential for Health Effects. J Biochem Mol Toxicol 2016; 30:375-95. [PMID: 27091632 DOI: 10.1002/jbt.21801] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2015] [Revised: 02/19/2016] [Accepted: 02/25/2016] [Indexed: 12/22/2022]
Abstract
New paradigms for human health risk assessment of environmental chemicals emphasize the use of molecular methods and human-derived cell lines. In this study, we examined the effects of the insect repellent DEET (N,N-diethyl-m-toluamide) and the phenylpyrazole insecticide fipronil (fluocyanobenpyrazole) on transcript levels in primary human hepatocytes. These chemicals were tested individually and as a mixture. RNA-Seq showed that 100 μM DEET significantly increased transcript levels (α = 0.05) for 108 genes and lowered transcript levels for 64 genes and fipronil at 10 μM increased the levels of 2246 transcripts and decreased the levels for 1428 transcripts. Fipronil was 21-times more effective than DEET in eliciting changes, even though the treatment concentration was 10-fold lower for fipronil versus DEET. The mixture of DEET and fipronil produced a more than additive effect (levels increased for 3017 transcripts and decreased for 2087 transcripts). The transcripts affected for all chemical treatments were classified by GO analysis and mapped to chromosomes. The overall treatment responses, specific pathways, and individual transcripts affected were discussed at different levels of fold-change. Changes found in transcript levels in response to treatments will require further research to understand their importance in overall cellular, organ, and organismic function.
Collapse
Affiliation(s)
- Robert D Mitchell
- Department of Entomology, Toxicology Program, Department of Biology, North Carolina State University, Raleigh, NC, 27695, USA
| | - Anirudh Dhammi
- Department of Entomology, North Carolina State University, Raleigh, NC, 27695, USA
| | - Andrew Wallace
- Toxicology Program, Department of Biology, North Carolina State University, Raleigh, NC, 27695, USA
| | - Ernest Hodgson
- Department of Applied Ecology, Toxicology Program, Department of Biology, North Carolina State University, Raleigh, NC, 27695, USA
| | - R Michael Roe
- Department of Entomology, Toxicology Program, Department of Biology, North Carolina State University, Raleigh, NC, 27695, USA.
| |
Collapse
|
17
|
Zhu J, Khalil SM, Mitchell RD, Bissinger BW, Egekwu N, Sonenshine DE, Roe RM. Mevalonate-Farnesal Biosynthesis in Ticks: Comparative Synganglion Transcriptomics and a New Perspective. PLoS One 2016; 11:e0141084. [PMID: 26959814 PMCID: PMC4785029 DOI: 10.1371/journal.pone.0141084] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2015] [Accepted: 10/03/2015] [Indexed: 11/19/2022] Open
Abstract
Juvenile hormone (JH) controls the growth, development, metamorphosis, and reproduction of insects. For many years, the general assumption has been that JH regulates tick and other acarine development and reproduction the same as in insects. Although researchers have not been able to find the common insect JHs in hard and soft tick species and JH applications appear to have no effect on tick development, it is difficult to prove the negative or to determine whether precursors to JH are made in ticks. The tick synganglion contains regions which are homologous to the corpora allata, the biosynthetic source for JH in insects. Next-gen sequencing of the tick synganglion transcriptome was conducted separately in adults of the American dog tick, Dermacentor variabilis, the deer tick, Ixodes scapularis, and the relapsing fever tick, Ornithodoros turicata as a new approach to determine whether ticks can make JH or a JH precursor. All of the enzymes that make up the mevalonate pathway from acetyl-CoA to farnesyl diphosphate (acetoacetyl-CoA thiolase, HMG-S, HMG-R, mevalonate kinase, phosphomevalonate kinase, diphosphomevalonate decarboxylase, and farnesyl diphosphate synthase) were found in at least one of the ticks studied but most were found in all three species. Sequence analysis of the last enzyme in the mevalonate pathway, farnesyl diphosphate synthase, demonstrated conservation of the seven prenyltransferase regions and the aspartate rich motifs within those regions typical of this enzyme. In the JH branch from farnesyl diphosphate to JH III, we found a putative farnesol oxidase used for the conversion of farnesol to farnesal in the synganglion transcriptome of I. scapularis and D. variabilis. Methyltransferases (MTs) that add a methyl group to farnesoic acid to make methyl farnesoate were present in all of the ticks studied with similarities as high as 36% at the amino acid level to insect JH acid methyltransferase (JHAMT). However, when the tick MTs were compared to the known insect JHAMTs from several insect species at the amino acid level, the former lacked the farnesoic acid binding motif typical in insects. The P450s shown in insects to add the C10,11 epoxide to methyl farnesoate, are in the CYP15 family; this family was absent in our tick transcriptomes and in the I. scapularis genome, the only tick genome available. These data suggest that ticks do not synthesize JH III but have the mevalonate pathway and may produce a JH III precursor.
Collapse
Affiliation(s)
- Jiwei Zhu
- Department of Entomology, North Carolina State University, Raleigh, North Carolina, 27695, United States of America
| | - Sayed M. Khalil
- Department of Entomology, North Carolina State University, Raleigh, North Carolina, 27695, United States of America
| | - Robert D. Mitchell
- Department of Entomology, North Carolina State University, Raleigh, North Carolina, 27695, United States of America
| | - Brooke W. Bissinger
- Department of Entomology, North Carolina State University, Raleigh, North Carolina, 27695, United States of America
| | - Noble Egekwu
- Department of Biological Sciences, Old Dominion University, Norfolk, Virginia, 23529, United States of America
| | - Daniel E. Sonenshine
- Department of Biological Sciences, Old Dominion University, Norfolk, Virginia, 23529, United States of America
| | - R. Michael Roe
- Department of Entomology, North Carolina State University, Raleigh, North Carolina, 27695, United States of America
- * E-mail:
| |
Collapse
|
18
|
Terrapon N, Li C, Robertson HM, Ji L, Meng X, Booth W, Chen Z, Childers CP, Glastad KM, Gokhale K, Gowin J, Gronenberg W, Hermansen RA, Hu H, Hunt BG, Huylmans AK, Khalil SMS, Mitchell RD, Munoz-Torres MC, Mustard JA, Pan H, Reese JT, Scharf ME, Sun F, Vogel H, Xiao J, Yang W, Yang Z, Yang Z, Zhou J, Zhu J, Brent CS, Elsik CG, Goodisman MAD, Liberles DA, Roe RM, Vargo EL, Vilcinskas A, Wang J, Bornberg-Bauer E, Korb J, Zhang G, Liebig J. Molecular traces of alternative social organization in a termite genome. Nat Commun 2014; 5:3636. [PMID: 24845553 DOI: 10.1038/ncomms4636] [Citation(s) in RCA: 268] [Impact Index Per Article: 26.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2013] [Accepted: 03/13/2014] [Indexed: 01/28/2023] Open
Abstract
Although eusociality evolved independently within several orders of insects, research into the molecular underpinnings of the transition towards social complexity has been confined primarily to Hymenoptera (for example, ants and bees). Here we sequence the genome and stage-specific transcriptomes of the dampwood termite Zootermopsis nevadensis (Blattodea) and compare them with similar data for eusocial Hymenoptera, to better identify commonalities and differences in achieving this significant transition. We show an expansion of genes related to male fertility, with upregulated gene expression in male reproductive individuals reflecting the profound differences in mating biology relative to the Hymenoptera. For several chemoreceptor families, we show divergent numbers of genes, which may correspond to the more claustral lifestyle of these termites. We also show similarities in the number and expression of genes related to caste determination mechanisms. Finally, patterns of DNA methylation and alternative splicing support a hypothesized epigenetic regulation of caste differentiation.
Collapse
Affiliation(s)
- Nicolas Terrapon
- 1] Institute for Evolution and Biodiversity, Westfälische Wilhelms-Universität, Münster D48149, Germany [2] [3]
| | - Cai Li
- 1] China National GeneBank, BGI-Shenzhen, Shenzhen 518083, China [2] Centre for GeoGenetics, Natural History Museum of Denmark, University of Copenhagen, Øster Voldgade 5-7, Copenhagen 1350, Denmark [3]
| | - Hugh M Robertson
- Department of Entomology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
| | - Lu Ji
- China National GeneBank, BGI-Shenzhen, Shenzhen 518083, China
| | - Xuehong Meng
- China National GeneBank, BGI-Shenzhen, Shenzhen 518083, China
| | - Warren Booth
- 1] Department of Entomology and W. M Keck Center for Behavioral Biology, North Carolina State University, Raleigh, North Carolina 27695, USA [2]
| | - Zhensheng Chen
- China National GeneBank, BGI-Shenzhen, Shenzhen 518083, China
| | | | - Karl M Glastad
- School of Biology, Georgia Institute of Technology, Atlanta, Georgia 30332, USA
| | - Kaustubh Gokhale
- School of Life Sciences, Arizona State University, Tempe, Arizona 85287, USA
| | - Johannes Gowin
- 1] Behavioural Biology, University of Osnabrück, Osnabrück D49076, Germany [2]
| | - Wulfila Gronenberg
- Department of Neuroscience, University of Arizona, Tucson, Arizona 85721, USA
| | - Russell A Hermansen
- Department of Molecular Biology, University of Wyoming, Laramie, Wyoming 82071, USA
| | - Haofu Hu
- China National GeneBank, BGI-Shenzhen, Shenzhen 518083, China
| | - Brendan G Hunt
- 1] School of Biology, Georgia Institute of Technology, Atlanta, Georgia 30332, USA [2]
| | - Ann Kathrin Huylmans
- 1] Institute for Evolution and Biodiversity, Westfälische Wilhelms-Universität, Münster D48149, Germany [2]
| | - Sayed M S Khalil
- 1] Department of Entomology and W. M Keck Center for Behavioral Biology, North Carolina State University, Raleigh, North Carolina 27695, USA [2] Department of Microbial Molecular Biology, Agricultural Genetic Engineering Research Institute, Giza 12619, Egypt
| | - Robert D Mitchell
- Department of Entomology and W. M Keck Center for Behavioral Biology, North Carolina State University, Raleigh, North Carolina 27695, USA
| | - Monica C Munoz-Torres
- Genomics Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Julie A Mustard
- School of Life Sciences, Arizona State University, Tempe, Arizona 85287, USA
| | - Hailin Pan
- China National GeneBank, BGI-Shenzhen, Shenzhen 518083, China
| | - Justin T Reese
- Division of Animal Sciences, University of Missouri, Columbia, Missouri 65211, USA
| | - Michael E Scharf
- Department of Entomology, Purdue University, West Lafayette, Indiana 47907, USA
| | - Fengming Sun
- China National GeneBank, BGI-Shenzhen, Shenzhen 518083, China
| | - Heiko Vogel
- Department of Entomology, Max Planck Institute for Chemical Ecology, Jena D-07745, Germany
| | - Jin Xiao
- China National GeneBank, BGI-Shenzhen, Shenzhen 518083, China
| | - Wei Yang
- China National GeneBank, BGI-Shenzhen, Shenzhen 518083, China
| | - Zhikai Yang
- China National GeneBank, BGI-Shenzhen, Shenzhen 518083, China
| | - Zuoquan Yang
- China National GeneBank, BGI-Shenzhen, Shenzhen 518083, China
| | - Jiajian Zhou
- China National GeneBank, BGI-Shenzhen, Shenzhen 518083, China
| | - Jiwei Zhu
- Department of Entomology and W. M Keck Center for Behavioral Biology, North Carolina State University, Raleigh, North Carolina 27695, USA
| | - Colin S Brent
- Arid Land Agricultural Research Center, United States Department of Agriculture, Maricopa, Arizona 85138, USA
| | - Christine G Elsik
- 1] Division of Animal Sciences, University of Missouri, Columbia, Missouri 65211, USA [2] Division of Plant Sciences, University of Missouri, Columbia, Missouri 65211, USA
| | | | - David A Liberles
- Department of Molecular Biology, University of Wyoming, Laramie, Wyoming 82071, USA
| | - R Michael Roe
- Department of Entomology and W. M Keck Center for Behavioral Biology, North Carolina State University, Raleigh, North Carolina 27695, USA
| | - Edward L Vargo
- Department of Entomology and W. M Keck Center for Behavioral Biology, North Carolina State University, Raleigh, North Carolina 27695, USA
| | - Andreas Vilcinskas
- Institut für Phytopathologie und Angewandte Zoologie, Justus-Liebig-Universität Giessen, Giessen D35390, Germany
| | - Jun Wang
- 1] China National GeneBank, BGI-Shenzhen, Shenzhen 518083, China [2] Department of Biology, University of Copenhagen, Copenhagen DK-1165, Denmark [3] Princess Al Jawhara Center of Excellence in the Research of Hereditary Disorders, King Abdulaziz University, 21589 Jeddah, Saudi Arabia [4] Macau University of Science and Technology, Avenida Wai long, Taipa, Macau 999078, China [5] Department of Medicine, University of Hong Kong, Hong Kong
| | - Erich Bornberg-Bauer
- Institute for Evolution and Biodiversity, Westfälische Wilhelms-Universität, Münster D48149, Germany
| | - Judith Korb
- 1] Behavioural Biology, University of Osnabrück, Osnabrück D49076, Germany [2]
| | - Guojie Zhang
- 1] China National GeneBank, BGI-Shenzhen, Shenzhen 518083, China [2] Centre for Social Evolution, Department of Biology, University of Copenhagen, Universitetsparken 15, DK-2100 Copenhagen, Denmark
| | - Jürgen Liebig
- School of Life Sciences, Arizona State University, Tempe, Arizona 85287, USA
| |
Collapse
|
19
|
Khalil SMS, Donohue KV, Thompson DM, Jeffers LA, Ananthapadmanaban U, Sonenshine DE, Mitchell RD, Roe RM. Full-length sequence, regulation and developmental studies of a second vitellogenin gene from the American dog tick, Dermacentor variabilis. J Insect Physiol 2011; 57:400-408. [PMID: 21192946 DOI: 10.1016/j.jinsphys.2010.12.008] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2010] [Revised: 12/16/2010] [Accepted: 12/20/2010] [Indexed: 05/30/2023]
Abstract
Vitellogenin (Vg) is the precursor of vitellin (Vn) which is the major yolk protein in eggs. In a previous report, we isolated and characterized the first Vg message from the American dog tick Dermacentor variabilis. In the current study, we describe a second Vg gene from the same tick. The Vg2 cDNA is 5956 nucleotides with a 5775 nt open reading frame coding for 1925 amino acids. The conceptual amino acid translation contains a 16-residues putative signal peptide, N-terminal lipid binding domain and C-terminal von Willebrand factor type D domain present in all known Vgs. Moreover, the amino acid sequence shows a typical GLCG domain and several RXXR cleavage sites present in most isolated Vgs. Tryptic digest-mass fingerprinting of Vg and Vn recognized 11 fragments that exist in the amino acid translation of DvVg2 cDNA. Injection of virgin females with 20 hydroxyecdysone induced DvVg2 expression, vitellogenesis and oviposition. Using RT-PCR, DvVg2 expression was detected only in tick females after mating and feeding to repletion. Northern blot analysis showed that DvVg2 is expressed in fat body and gut cells of vitellogenic females but not in the ovary. DvVg2 expression was not detected in adult fed or unfed males. The characteristics that distinguish Vg from other similar tick storage proteins like the carrier protein, CP (another hemelipoglycoprotein) are discussed.
Collapse
Affiliation(s)
- Sayed M S Khalil
- Department of Entomology, North Carolina State University, Raleigh, NC 27695-7647, USA
| | | | | | | | | | | | | | | |
Collapse
|
20
|
Donohue KV, Khalil SMS, Ross E, Mitchell RD, Roe RM, Sonenshine DE. Male engorgement factor: Role in stimulating engorgement to repletion in the ixodid tick, Dermacentor variabilis. J Insect Physiol 2009; 55:909-918. [PMID: 19538967 DOI: 10.1016/j.jinsphys.2009.05.019] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2009] [Revised: 05/21/2009] [Accepted: 05/21/2009] [Indexed: 05/27/2023]
Abstract
Mating in ticks results in profound physiological changes that eventually results in egg production. In the American dog tick, Dermacentor variabilis, mating causes partially blood-fed female ticks to commence rapid engorgement to repletion and eventual detachment from the host and egg laying. The peptidic male pheromone (engorgement factor alpha/beta) transferred to the female during mating is known only from a single tick species, Amblyomma hebraeum, and was shown to consist of two peptides produced in the testis/vas deferens (TVD) and not in the male accessory gland (MAG). In the current study, we obtained 2704bp of sequence data for efalpha from D. variabilis, of 7kb as determined by Northern blot, and show that it is also present in the Southern cattle tick, Rhipicephalus microplus and the deer tick, Ixodes scapularis. Analysis of the male gonad transcriptome by pyrosequencing produced 563,093 reads of which 636 matched with efalpha; none matched with efbeta. No evidence of efbeta orthologs could be found in any publicly available database including the I. scapularis genome. Silencing efalpha in male ticks failed to significantly reduce the engorgement weight of females compared to controls. Injection of sephadex beads, replete female synganglia, fed male MAG, fed male TVD, or replete female vagina/seminal receptacle (VA/SR), separately, failed to initiate feeding to repletion like that found in normally mated females. However, a small percentage of females injected with VA/SR that fed beyond the arbitrary weight for repletion of 300mg, produced brown eggs (an indication of vitellogenin uptake by the oocytes). The greatest effect was observed in female ticks injected with a suspension of MAG and TVD combined; 50% fed to repletion and all of these dropped off from the host and laid brown eggs. The effect was abolished if the aqueous fraction of the MAG/TVD homogenate only was injected suggesting that EF in ticks is a non-secreted membrane-bound or intracellular protein. Overall, these data suggest that EFalpha in D. variabilis is not an engorgement factor.
Collapse
Affiliation(s)
- Kevin V Donohue
- Department of Entomology, North Carolina State University, Raleigh, 27695-7647, USA
| | | | | | | | | | | |
Collapse
|
21
|
Abstract
A case of intramedullary spinal metastasis presenting 14 months after excision of the primary anaplastic cerebral oligodendroglioma is presented. To the best of our knowledge, less than 10 cases of spinal metastasis have been reported in the world literature.
Collapse
Affiliation(s)
- C W McBryde
- Neuroscience Centre, Queen Elizabeth Hospital, Edgbaston, Birmingham, UK
| | | | | |
Collapse
|
22
|
Donohue KV, Khalil SMS, Mitchell RD, Sonenshine DE, Roe RM. Molecular characterization of the major hemelipoglycoprotein in ixodid ticks. Insect Mol Biol 2008; 17:197-208. [PMID: 18477238 DOI: 10.1111/j.1365-2583.2008.00794.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
The major hemelipoglyco-carrier protein (CP) found throughout the development of male and female adult American dog ticks, Dermacentor variabilis (Say) was sequenced. DvCP is a single transcript coding for two protein subunits that together contain three motifs: (1) a lipoprotein n-terminal domain that is a common attribute of proteins that bind lipids, carbohydrates and metals; (2) a domain of unknown function characteristic of proteins with several large open beta sheets; and (3) a von Willebrand factor type D domain near the carboxy-terminus apparently important for multimerization. These motifs, which are also found in tick vitellogenin, are not shared by heme-binding proteins studied thus far in other hematophagous insects. DvCP message was highest in fat body and salivary gland but was also found in midgut and ovary tissue. Expression was initiated by blood feeding in virgin females and not by mating, as is typical of tick vitellogenin; and the message was found in fed males at levels similar to part fed, virgin females. CP appears to be highly conserved among the Ixodida. The closest match by BlastP to DvCP is vitellogenin from Caenorhabditis elegans (AAC04423), suggesting that CP is a novel protein. The role of CP in heme sequestration, the evolution of hematophagy and host complementation are discussed.
Collapse
Affiliation(s)
- K V Donohue
- Department of Entomology, North Carolina State University, Raleigh, NC 27695, USA
| | | | | | | | | |
Collapse
|
23
|
Hillis JM, Mitchell RD. Informing prospective medical students. Med J Aust 2008; 188:431. [DOI: 10.5694/j.1326-5377.2008.tb01705.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2008] [Accepted: 02/05/2008] [Indexed: 11/17/2022]
|
24
|
Thompson DM, Khalil SMS, Jeffers LA, Sonenshine DE, Mitchell RD, Osgood CJ, Michael Roe R. Sequence and the developmental and tissue-specific regulation of the first complete vitellogenin messenger RNA from ticks responsible for heme sequestration. Insect Biochem Mol Biol 2007; 37:363-74. [PMID: 17368200 DOI: 10.1016/j.ibmb.2007.01.004] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2006] [Revised: 01/03/2007] [Accepted: 01/03/2007] [Indexed: 05/14/2023]
Abstract
The first full-length mRNA for vitellogenin (Vg) from ticks was sequenced. This also represents the first complete sequence of Vg from the Chelicerata and of a heme binding Vg. The Vg cDNA from the American dog tick, Dermacentor variabilis was 5744nt in length (GenBank Accession number AY885250), which coded for a protein of 1843 aa with a calculated molecular weight of 208 kD. This protein had an 18 aa signal sequence, a single RXXR cleavage signal that would generate two subunits (49.5 and 157K in molecular weight) and lipoprotein N-terminal and carboxy von Willebrand factor type D domains. Tryptic digest MS analysis of vitellin protein confirmed the function of the cDNA as the tick yolk protein. Apparently, vitellin in D. variabilis is oligomeric (possibly dimeric) and is comprised of a mixture of the uncleaved monomer and subunits that were predicted from the single RXXR cleavage signal. The highly conserved GL/ICG motif close to the C-terminus in insect Vg genes was different in the tick Vg message, i.e., GLCS. This variant was also present in a partial sequence of Vg from Boophilus microplus. Phylogenic analysis showed that the full length Vg cDNA from D. variabilis and the partial cDNA from B. microplus were distinct from insects and Crustacea. The Vg message was not found in whole body RNA from unfed or fed males or in unfed and partially fed (virgin) females as determined by Northern blotting. The message was found in replete (mated) pre-ovipositional females, increased to higher levels in ovipositing females and was absent after egg laying was complete. The endocrine regulation of the Vg mRNA is discussed. The tissue sources of the Vg message are both the gut and fat body. Tryptic digest MS fingerprinting suggests that a second Vg mRNA might be present in the American dog tick, which needs further study.
Collapse
Affiliation(s)
- Deborah M Thompson
- Department of Entomology, Campus Box 7647, North Carolina State University, Raleigh, NC 27695-7647, USA
| | | | | | | | | | | | | |
Collapse
|
25
|
Mitchell RD, Ross E, Osgood C, Sonenshine DE, Donohue KV, Khalil SM, Thompson DM, Michael Roe R. Molecular characterization, tissue-specific expression and RNAi knockdown of the first vitellogenin receptor from a tick. Insect Biochem Mol Biol 2007; 37:375-88. [PMID: 17368201 DOI: 10.1016/j.ibmb.2007.01.005] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2006] [Revised: 01/04/2007] [Accepted: 01/05/2007] [Indexed: 05/14/2023]
Abstract
This is the first full-length message for a vitellogenin receptor (VgR) sequenced from ticks. VgRs, members of the low-density lipoprotein receptor (LDLR) superfamily, mediate the uptake of the yolk protein, vitellogenin (Vg), from the hemolymph. The VgR message from the American dog tick, Dermacentor variabilis (GenBank accession No. DQ103506.4) comprised 5673 bp which coded for a 1798 aa deduced protein with a predicted 196.6 kDa molecular mass. After removing the 20 aa signal peptide, the 1778 aa deduced mature protein had a predicted 196.6 kDa molecular mass. BLAST comparisons showed the highest similarity to the VgR of the cockroach, Periplaneta americana. VgR message was expressed in mated female ovary but absent in female midgut and salivary glands or whole body mRNA from blood fed males, indicating that it is both sex and tissue specific. VgR transcript was absent in virgin (previtellogenic) females but present in ovaries of mated females following drop off. RNAi showed that unfed adult ticks injected with a VgR-dsRNA probe failed to lay eggs, develop brown eggs or fully express VgR transcript (Northern blots). In contrast, controls oviposited numerous normal brown eggs and showed strong expression of VgR transcripts. These results show that the expression of the VgR message is essential for Vg uptake and egg development in the American dog tick.
Collapse
Affiliation(s)
- Robert D Mitchell
- Department of Biological Sciences, Old Dominion University, Norfolk, VA 23529, USA
| | | | | | | | | | | | | | | |
Collapse
|
26
|
Vishwanath D, Mitchell RD, Wynne-Jones G, Rolfe E. Ventilation-perfusion imaging used to indicate the cause of a brain abscess. Clin Radiol 2007; 62:487-90. [PMID: 17398275 DOI: 10.1016/j.crad.2006.11.011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2006] [Revised: 11/22/2006] [Accepted: 11/24/2006] [Indexed: 11/19/2022]
Affiliation(s)
- D Vishwanath
- Department of Neurosurgery, Queen Elizabeth Hospital, Birmingham, UK
| | | | | | | |
Collapse
|
27
|
Kowlessar PI, O'Connell NH, Mitchell RD, Elliott S, Elliott TSJ. Management of patients with Streptococcus milleri brain abscesses. J Infect 2006; 52:443-50. [PMID: 16239034 DOI: 10.1016/j.jinf.2005.08.028] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/15/2005] [Indexed: 11/27/2022]
Abstract
OBJECTIVES We evaluated the efficacy of cefotaxime in the management of brain abscesses caused by Streptococcus milleri. Twenty two patients with a S. milleri brain abscess were treated with metronidazole and cefotaxime, in accordance with recent recommendations by the British Society Of Antimicrobial Chemotherapy (BSAC). Seven patients who had Glasgow Coma Scales < or =11 also received rifampicin and high dose cefotaxime. The clinical response of the patients was determined. METHOD A retrospective study at the Queen Elizabeth Hospital, Birmingham covering the period April 1996-March 2004 was carried out. Neurosurgical and anti-microbial therapeutic approaches were reviewed. Any evidence of improvement of clinical features and radiological disappearance of brain abscesses were determined. RESULTS Outcome was assessed using the Glasgow Outcome Score (GOS) at 3 and 6 months from the time of surgical intervention. Eighteen patients (82%) had a good outcome by 6 months, with an outcome score of 4-5. Thirteen patients resumed normal life despite minor deficits (GOS 5), while a further five patients had moderate disability though remained independent (GOS 4). One patient had a GOS of 3 and there were three deaths (14). The minimum time to radiological resolution of the abscess was within 1 month in six cases (27) These all represented solitary lesions that required a single drainage procedure in conjunction with 4 weeks of intravenous cefotaxime and metronidazole. Ten cases (45%) had resolution within 4 months and a further three cases took at least 6 months from the time of surgery to show radiological clearance. CONCLUSIONS This cohort of patients responded favourably to the guidelines recommended by the BSAC. This was confirmed by the Glasgow Outcome Score (GOS 4-5) at 6 months review. Cefotaxime at a higher dose with rifampicin was prescribed for patients presenting with a decreased conscious level (GCS 8-11), subsequent failure of anticipated clinical improvement or clinical deterioration. There was no clinically significant difference in GOS between the two treatment groups. An algorithm for management of brain abscess is presented, based on our clinical experience and review of the literature.
Collapse
Affiliation(s)
- P I Kowlessar
- Departments of Neurosurgery, Queen Elizabeth Hospital, Edgbaston, Birmingham, UK
| | | | | | | | | |
Collapse
|
28
|
Thompson DM, Khalil SMS, Jeffers LA, Ananthapadmanaban U, Sonenshine DE, Mitchell RD, Osgood CJ, Apperson CS, Michael Roe R. In vivo role of 20-hydroxyecdysone in the regulation of the vitellogenin mRNA and egg development in the American dog tick, Dermacentor variabilis (Say). J Insect Physiol 2005; 51:1105-16. [PMID: 16061249 DOI: 10.1016/j.jinsphys.2005.05.011] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2005] [Revised: 05/19/2005] [Accepted: 06/02/2005] [Indexed: 05/03/2023]
Abstract
Injection of the hormone 20-hydroxyecdysone (20-E) into partially fed (virgin) female adults of the American dog tick, Dermacentor variabilis, while they are attached and feeding on the rabbit host, initiated the expression of the vitellogenin (Vg) gene, and Vg protein secretion and uptake by the ovary. The induction of egg production by 20-E in this bioassay was dose dependent in the range of 1-50 times the concentration normally found in a replete, vitellogenic female. Ticks examined 4 d after the 50 x treatment were still attached to the host, had numerous enlarged vitellin-filled (brown) oocytes in their ovaries, but had not engorged to repletion. The ovaries reached weights similar to those found in untreated, replete (mated) females (pre-oviposition) while solvent-injected controls demonstrated no increase in oocyte size or increase in ovary weight. An increase in the levels of a putative Vg protein was observed in hemolymph samples collected 1, 2 and 3d post-20-E injection but was not observed in the corresponding solvent controls as determined by native PAGE. Analysis of the ecdysteroid-induced protein by tryptic digestion-mass fingerprinting and BLASTP found that the putative Vg had the strongest match to GP80 (U49934), the partial sequence for the vitellogenin protein from Boophilus microplus. A partial Vg cDNA was cloned and sequenced from replete females of D. variabilis with a high similarity to GP80. Using this message as a probe, Northern blots conducted with RNA collected from partially fed, virgin females 1, 2 and 3d post-20-E injection showed upregulation of the Vg mRNA on all 3 days. Controls injected with solvent only showed no Vg mRNA. Injections with juvenile hormone III did not stimulate Vg expression, oocyte growth or full engorgement. These studies indicate that ecdysteroids and not JH can initiate expression of the Vg gene, Vg protein synthesis and release into hemolymph, and Vg uptake into developing oocytes under bioassay conditions mimicking normal feeding on the host.
Collapse
Affiliation(s)
- Deborah M Thompson
- Department of Entomology, Campus Box 7647, North Carolina State University, Raleigh, NC 27695-7647, USA
| | | | | | | | | | | | | | | | | |
Collapse
|
29
|
Hamid NA, Mitchell RD, Mocroft P, Westby GWM, Milner J, Pall H. Targeting the subthalamic nucleus for deep brain stimulation: technical approach and fusion of pre- and postoperative MR images to define accuracy of lead placement. J Neurol Neurosurg Psychiatry 2005; 76:409-14. [PMID: 15716537 PMCID: PMC1739553 DOI: 10.1136/jnnp.2003.032029] [Citation(s) in RCA: 98] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
OBJECTIVES To define the role of magnetic resonance imaging (MRI) and intraoperative electrophysiological recording in targeting the subthalamic nucleus (STN) in Parkinson's disease and to determine accuracy of electrode placement. PATIENTS AND METHODS We implanted 54 electrodes into the STN in 27 patients. Target planning was done by coordinate guidelines and visualising the STN on MRI and defined in relation to the mid-point of the AC-PC line. Intraoperative microelectrode recording was used. We adjusted electrode positions for placement in the centre of the STN electrical activity and verified this on postoperative MRI in 16 cases, which were fused to the preoperative images to measure actual error in electrode placement in the three axes. RESULTS Based on coordinate calculation and MRI localisation, the mean of the target was 11.5 mm lateral, 2.5 mm posterior and 4.1 mm inferior to the mid-point of the AC-PC line. Fifty good electrophysiological recordings of the STN (average length 4.65 mm) were achieved and target point adjusted in 90% of lead placements. The mean of the final target after electrophysiological correction was 11.7 mm lateral, 2.1 mm posterior, and 3.8 mm inferior to the mid-point. The distance from the centre of the electrode artefact to the final target used after electrophysiological recording on the fused images was 0.48 mm, 0.69 mm, and 2.9 mm in the x, y, and z axes, respectively. No postoperative MRI related complication was observed. CONCLUSION Both direct visualisation of the STN on MRI and intraoperative electrophysiological recording are important in defining the best target. Individual variations exist in the location of the STN target. Fewer tracks were required to define STN activity on the side operated first. Our current stereotactic method of electrode placement is relatively accurate.
Collapse
Affiliation(s)
- N A Hamid
- Department of Neurosurgery, Queen Elizabeth Medical Centre, University Hospital Birmingham, Birmingham, B15 2TH, UK
| | | | | | | | | | | |
Collapse
|
30
|
Hoke TR, Donohue PK, Bawa PK, Mitchell RD, Pathak A, Rowe PC, Byrne BJ. Oxygen saturation as a screening test for critical congenital heart disease: a preliminary study. Pediatr Cardiol 2002; 23:403-9. [PMID: 12170356 DOI: 10.1007/s00246-002-1482-8] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The aim of this study was to assess the utility of arm and leg oxygen saturation as a candidate screening test for the early detection of ductal-dependent left heart obstructive disease. We measured arm and leg oxygen saturation in 2876 newborns admitted to well baby nurseries and 32 newborns with congenital heart disease. Fifty-seven newborns in the well baby nurseries (0.02%) had an abnormal test (leg saturation less than 92% in room air or 7% lower saturation in the leg than in the arm). Four of the 57 had critical congenital heart disease, including 1 with coarctation of the aorta. Of the 32 newborns with congenital heart disease, 11/13 (85%) with left heart obstructive disease had abnormal oxygen saturation tests, as did 15/19 (79%) with other forms of congenital heart disease. Pulse oximetry deserves further study as a screening test for critical congenital heart disease.
Collapse
Affiliation(s)
- T R Hoke
- Division of Neonatology, Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
| | | | | | | | | | | | | |
Collapse
|
31
|
Griffiths SJ, Jatavallabhula NS, Mitchell RD. Spontaneous extradural haematoma associated with craniofacial infections: case report and review of the literature. Br J Neurosurg 2002; 16:188-91. [PMID: 12046743 DOI: 10.1080/026886902317384553] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
A 17-year-old male with occult cleft palate presented with depressed-consciousness due to spontaneous frontal extradural haematoma associated with sinusitis. Craniotomy, evacuation of the haematoma and drainage of the frontal sinuses led to a full recovery. Spontaneous extradural haematomas secondary to craniofacial infections are very rare; this appears to be the first described with a coexisting congenital palatal abnormality. The diagnosis should be considered when signs of infection are present with depressed consciousness as a delay in treatment may result in death.
Collapse
Affiliation(s)
- S J Griffiths
- Department of Neurosurgery, Queen Elizabeth Hospital, Edgbaston, Birmingham, UK
| | | | | |
Collapse
|
32
|
Abstract
The effect of arsenic compounds depends on the chemical form and is specific for certain organs. The lack of specific biological indicators for the effects of each arsenic species makes it difficult to differentiate their toxicity. Five prospective biological indicators of systemic toxicity were examined at time points ranging from 15 min to 24 h using male Sprague-Dawley rats, B6C3F1 mice, Golden-Syrian hamsters, and Hartley guinea pigs, following intraperitoneal dosing with 0.1 and 1 mg/kg sodium arsenite. Rats and mice were also dosed with 1 mg/kg sodium arsenate. Total blood arsenic levels were determined in all animal species to show that exposure occurred and as an index of the severity of the change is an indicator of toxicity. Total blood arsenic levels were increased in all animal species. This increase was dose, arsenic species, and animal dependent. Renal pyruvate dehydrogenase activity was significantly decreased at early time points in mice, hamsters, and guinea pigs, and at later time points in rats dosed with arsenite. Rats and mice dosed with arsenate also exhibited PDH decrease at early time points. Blood hematocrit and glucose were increased in the rat and guinea pig, respectively, after arsenite administration. Creatinine and urea nitrogen were found to be unresponsive to arsenic in most animal species. Data suggested that the mouse and secondly the hamster appear to be the most appropriate animal models for the study of acute arsenic toxicity.
Collapse
Affiliation(s)
- R D Mitchell
- Department of Pharmacology and Toxicology, Center for Toxicology's Superfund Basic Research Program, College of Pharmacy, University of Arizona, Tucson 85721, USA
| | | | | |
Collapse
|
33
|
Affiliation(s)
- Z Novak
- Department of Radiology, Denver Health Medical Center, Colorado, USA
| | | | | | | | | |
Collapse
|
34
|
Affiliation(s)
- J E Norman
- The St George Private Medical Centre, Kogarah NSW, Australia
| | | |
Collapse
|
35
|
Abstract
Corynebacterium pseudotuberculosis is a well recognised pathogen of farm animals, particularly sheep and goats. Human infection is a rare occurrence. This report describes suppurative lymphadenitis occurring in an adolescent boy who had contact with farm animals. The histological differential diagnosis of suppurative granulomatous lymphadenitis is discussed, and the importance of lymph node culture is stressed.
Collapse
Affiliation(s)
- A E Mills
- Dorevitch Pathology, Bendigo Hospital, Vic, Australia
| | | | | |
Collapse
|
36
|
Mitchell RD, Edwards HM, McDaniel GR, Rowland GN. Dietary 1,25-dihydroxycholecalciferol has variable effects on the incidences of leg abnormalities, plasma vitamin D metabolites, and vitamin D receptors in chickens divergently selected for tibial dyschondroplasia. Poult Sci 1997; 76:338-45. [PMID: 9057217 DOI: 10.1093/ps/76.2.338] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Three experiments were conducted to examine the efficacy of dietary 1,25-dihydroxycholecalciferol [(1,25-(OH)2D3)] on the development of tibial dyschondroplasia (TD) in chickens divergently selected for high (HTD) and low (LTD) incidences of TD. In Experiment 1, chickens from the two lines were fed two calcium levels (0.75 and 1.0%), with and without 5 micrograms/ kg dietary 1,25-(OH)2D3. In Experiment 2, both lines were fed diets containing 1.0% calcium and 0, 5, 10, or 15 micrograms/kg 1,25-(OH)2D3. The addition of 1,25-(OH)2D3 did not reduce the overall incidence of TD in Experiment 1, but did reduce the incidence of severe TD from 69 to 48% in the chickens receiving the 0.75% calcium diet. In this experiment, LTD chickens had higher plasma phosphorus and bone ash. No line differences were noted between plasma vitamin D metabolites or intestinal vitamin D receptors. In Experiment 2, 5 micrograms/kg of 1,25-(OH)2D3 decreased the incidence of TD from 94 to 76% and number three scores from 69 to 44% (P < or = 0.001). Higher amounts of 1,25-(OH)2D3 further decreased TD, but there was a reduction in body weight above 5 micrograms/kg. Plasma 25-hydroxycholecalciferol [25-(OH)D3] and 1,25-(OH)2D3 were higher and intestinal vitamin D receptors were lower in HTD chickens than in LTD chickens. Plasma 1,25-(OH)2D3 was not affected by dietary treatment, but 25-(OH)D3 was reduced by dietary 1,25-(OH)2D3. Experiment 3 was conducted to examine effects of line and dietary 1,25-(OH)2D3 on plasma vitamin D metabolites and intestinal and growth plate receptors. No effect of genetic line or dietary 1,25-(OH)2D3 was observed for vitamin D receptors concentration or plasma 1,25-(OH)2D3 levels. Plasma 25-(OH)D3 was reduced when 1,25-(OH)2D3 was fed. These results indicate that HTD chickens are somewhat responsive to dietary 1,25-(OH)2D3, but this treatment failed to prevent the lesion in a large portion of the population.
Collapse
Affiliation(s)
- R D Mitchell
- Department of Poultry Science, University of Georgia, Athens 30602, USA
| | | | | | | |
Collapse
|
37
|
Mitchell RD, Edwards HM, McDaniel GR. The effects of ultraviolet light and cholecalciferol and its metabolites on the development of leg abnormalities in chickens genetically selected for a high and low incidence of tibial dyschondroplasia. Poult Sci 1997; 76:346-54. [PMID: 9057218 DOI: 10.1093/ps/76.2.346] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Four experiments were conducted to investigate the effects of ultraviolet (UV) light exposure and several cholecalciferol metabolites on the development of tibial dyschondroplasia (TD) and other parameters associated with vitamin D metabolism in chickens selected for high (HTD) and low (LTD) incidence of TD. In Experiment 1, exposure of chickens to UV light reduced the incidence and severity of TD more in LTD chickens than in HTD chickens, as evident by the significant interactions (P < 0.10 and 0.04). In Experiment 2, the addition of cholecalciferol to diets that were deficient in cholecalciferol linearly decreased the incidence of vitamin D rickets and increased bone ash, but increased the incidence of severe TD. The LTD chickens had a higher maximal bone ash of 40.0 +/- 0.7% than did the HTD chickens, which had a maximal bone ash of 37.0 +/- 0.7%. In Experiment 3, the addition of 5 micrograms/kg of 25-hydroxycholecalciferol [25-(OH)D3], 1-alpha-hydroxycholecalciferol, or 1,25- dihydroxycholecalciferol decreased the incidence and severity of TD in the LTD chickens and had no effect on TD in HTD chickens. In Experiment 4, increasing dietary 25-(OH)D3 increased plasma 25-(OH)D3 levels in both lines, but HTD chickens had higher plasma 25-(OH)D3 levels at 20 and 40 micrograms/kg of dietary 25-(OH)D3. The incidence and severity of TD were reduced in the LTD chickens by dietary 25-(OH)D3, but little effect was noted in HTD chickens. The LTD chickens reached a maximal bone ash at 9.7 +/- 1.9 micrograms/kg and HTD chickens reached the same bone ash at 33.0 +/- 7.0 micrograms/kg. These results indicate that UV light and vitamin D metabolites are not effective in preventing TD in HTD chickens, but that altered vitamin D metabolism does exist between HTD and LTD chickens.
Collapse
Affiliation(s)
- R D Mitchell
- Department of Poultry Science, University of Georgia, Athens 30602-2772, USA
| | | | | |
Collapse
|
38
|
Daly GM, Mitchell RD. Case management in the community setting. Nurs Clin North Am 1996; 31:527-34. [PMID: 8751786] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
This article describes a federally funded nurse managed community health organization that treats the elderly. The innovative community-focused model uses the nurse as case manager to provide health promotion, screening, and early interventions to clients enrolled in the Community Nursing Organization (CNO). It explains the advantages of integrating advanced practice nurses into the nursing staff to provide both direct care to clients and teaching/conculation to the nursing staff. The CNO demonstrates that advanced practice nurses possess autonomous practice skills and are able to integrate preventive and curative care across practice sites.
Collapse
Affiliation(s)
- G M Daly
- Community Nursing Organization, Visiting Nurse Service of New York, Long Island City, USA
| | | |
Collapse
|
39
|
Mitchell RD, Edwards HM. Effects of phytase and 1,25-dihydroxycholecalciferol on phytate utilization and the quantitative requirement for calcium and phosphorus in young broiler chickens. Poult Sci 1996; 75:95-110. [PMID: 8650118 DOI: 10.3382/ps.0750095] [Citation(s) in RCA: 77] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Three experiments were conducted to determine the effects of supplementing 1,25-dihydroxycholecalciferol [1,25-(OH)2D3] and a commercial phytase product on Ca and P requirements of 0- to 21-d-old broiler males. These experiments were conducted with four levels of dietary Ca and P in corn-soybean diets with and without supplementation of 5 micrograms/kg of 1,25-(OH)2D3, 600 units/kg of phytase, and the combination of these supplements. The results show that these levels of phytase and 1,25-(OH)2D3 can replace up to 0.1% of the inorganic P for criteria such as BW, bone ash, and plasma P. Both supplements increased phytate P retention, whereas higher levels of Ca and P decreased phytate P retention. The addition of 1,25-(OH)2D3, but not phytase, reduced Ca requirements and decreased the incidence of tibial dyschondroplasia. The combination of these levels of phytase and 1,25-(OH)2D3 replaced 0.2% inorganic P for criteria such as BW, bone ash, and P rickets. Total dietary P requirements are estimated to be between 0.55 and 0.60% at the levels of phytase and 1,25-(OH)2D3, listed above, or 0.45% when the combination is added. The Ca requirements are estimated to be 0.77% when 1,25-(OH)2D3 is added to the diet and 0.9 to 0.95% when phytase is added.
Collapse
Affiliation(s)
- R D Mitchell
- Department of Poultry Science, University of Georgia, Athens 30602-2772, USA
| | | |
Collapse
|
40
|
Mitchell RD, Edwards HM. Additive effects of 1,25-dihydroxycholecalciferol and phytase on phytate phosphorus utilization and related parameters in broiler chickens. Poult Sci 1996; 75:111-9. [PMID: 8650100 DOI: 10.3382/ps.0750111] [Citation(s) in RCA: 54] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Two experiments were conducted to compare the effects of supplementation with 1,25-dihydroxycholecalciferol [1,25-(OH)2D3] and a commercial phytase on P utilization by broiler males. Experiment 1 was conducted with three levels of total dietary P (0.45,0.55, and 0.65%) in corn-soybean meal diets supplemented with 5 micrograms/kg of 1,25-(OH)2D3, 600 units/kg of phytase, or the combination of these supplements in a factorial arrangement from 0 to 21 d in battery brooders. A second experiment was conducted with a similar design except that it was carried out in floor pens for a period of 35 d. In Experiment 1, maximal BW was obtained at 0.65% P in chicks receiving the basal diet, 0.55% P in chicks receiving phytase or 1,25-(OH)2D3, and 0.45% P in chicks fed both supplements. Bone ash for chicks receiving the basal, phytase, 1,25-(OH)2D3, and combination treatments at 0.45% total dietary P were 26.6, 34.9, 35.1, and 38.8%. There were significant interactions between phytase and 1,25-(OH)2D3 for BW, bone ash, and incidence of rickets. Similar results were noticed in Experiment 2, with the exception that 1,25-(OH)2D3 had little influence on BW from 0 to 3 wk, likely due to slightly higher dietary P. From 3 to 5 wk, BW and bone ash were increased by each supplement and further increased by their combination. These interactions suggest different mechanisms of action for these supplements in influencing phytate P utilization.
Collapse
Affiliation(s)
- R D Mitchell
- Department of Poultry Science, University of Georgia, Athens 30602-2772, USA
| | | |
Collapse
|
41
|
Mitchell RD, Jessup S. Staying one step ahead--development of an electronic record. Caring 1995; 14:34, 37, 39-41. [PMID: 10151216] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
Participation in a demonstration program allowed the VNS of New York to develop its own electronic records system. This description of the process and the resulting system should give a good picture of the ultimate benefits of such a system.
Collapse
|
42
|
Kanwar S, Mitchell RD, Foy PM. Meningitis occurring 39 years after head injury, secondary to rupture of a mucocele. Injury 1995; 26:355-6. [PMID: 7649662 DOI: 10.1016/0020-1383(95)00035-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- S Kanwar
- Department of Clinical Neurosciences, Western General Hospital, Edinburgh, UK
| | | | | |
Collapse
|
43
|
Glass DB, Trewhella J, Mitchell RD, Walsh DA. Conformationally constrained analogs of protein kinase inhibitor (6-22)amide: effect of turn structures in the center of the peptide on inhibition of cAMP-dependent protein kinase. Protein Sci 1995; 4:405-15. [PMID: 7795524 PMCID: PMC2143090 DOI: 10.1002/pro.5560040307] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The high-affinity interaction between protein kinase inhibitor (PKI)(6-22)amide(Thr6-Tyr-Ala-Asp-Phe-Ile-Ala-Ser-Gly-Arg-Thr-Gly- Arg-Arg-Asn- Ala-Ile22-NH2) and the catalytic subunit of cAMP-dependent protein kinase requires both the N-terminal Thr6 to Ile11 sequence of the inhibitor peptide and its C-terminal pseudosubstrate site comprised of Arg15 to Ile22. Small angle X-ray scattering data indicate that PKI(6-22)amide has a compact, rather than extended, structure in solution (Reed J et al., 1989, Biochem J 264:371-380). CD spectroscopic analysis of the PKI peptide led to the suggestion that a beta-turn structure might be located in the -Ala12-Ser-Gly-Arg15-connecting sequence in the middle of the molecule (Reed J, Kinzel V, Cheng HC, Walsh DA, 1987, Biochemistry 26:7641-7647). To investigate this possibility further, conformationally constrained and flexible analogs of PKI(6-22)amide were synthesized and used to study the structure-function relationships of this central portion of the inhibitor. (Des12-14)PKI(6-22) amide exhibited over a 200-fold loss in inhibitory activity. Replacement of the omitted -Ala12-Ser-Gly14-sequence with aminocaprylic acid yielded an analog that regained more than 90% of the lost binding energy. The D-alanine14 PKI analog was as potent as the parent peptide, whereas the beta-alanine14 and the sarcosine14 analogs were only 10-fold less active. Several peptides that promoted a beta-turn structure at residues 12-15 showed about 200-fold decreases in inhibitory activity. Two constrained analogs that could not assume a beta-turn conformation were only 30-fold less potent than PKI(6-22)amide. Thus, the structure of the central connecting portion of the PKI peptide, encompassing residues 12-15, greatly influences its ability to effectively bind to and inhibit the catalytic subunit. We conclude, however, that a formal beta-turn at this position is not required and is actually detrimental for a high-affinity interaction of PKI(6-22)amide with the enzyme. These results are interpreted in light of the Fourier-transform infrared spectra of the peptide analogs and the crystal structure of the peptide bound at the active site of the protein kinase (Knighton DR et al., 1991b, Science 253:414-420).
Collapse
Affiliation(s)
- D B Glass
- Department of Pharmacology, Emory University School of Medicine, Atlanta, Georgia 30322, USA
| | | | | | | |
Collapse
|
44
|
Mitchell RD, Glass DB, Wong CW, Angelos KL, Walsh DA. Heat-stable inhibitor protein derived peptide substrate analogs: phosphorylation by cAMP-dependent and cGMP-dependent protein kinases. Biochemistry 1995; 34:528-34. [PMID: 7819246 DOI: 10.1021/bi00002a018] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The phosphorylation of substrate peptides derived from PKI, the heat-stable inhibitor protein of the cAMP-dependent protein kinase (PKA), has been studied with both PKA and the cGMP-dependent protein kinase (PKG) using a variety of substitution and deletion analogs. On the basis of Km, kcat and kcat/Km values, (Ser21)PKI alpha(14-22) amide (numbering based upon native PKI alpha) is the most effective peptide substrate yet discovered for either kinase, although other peptides, while phosphorylated considerably less efficiently by PKG, are more specific. Although the inhibitory peptide corresponding to this sequence (i.e., with an Ala at position 21) is a much more potent inhibitor of PKA than of PKG (approximately 250-fold), PKG actually exhibits a 60% higher kcat than does PKA with the (Ser21)PKI alpha(14-22) amide substrate peptide, with only a 20-fold higher Km value. The two key PKI residues within this peptide which were found to be essential for substrate activity with both kinases were Arg18 (P-3) and Ile22 (P+1). The Arg19 (P-2) residue, which contributes significantly to both PKI-based peptide inhibitors and substrates of PKA, was only a more minor contributor to PKG substrate efficacy. Of particular note, the Phe10 (P-11) residue, which contributes very substantially to high affinity binding of both PKI and longer PKI peptide inhibitors, neither positively nor negatively affects the kinetics of either PKA or PKG with PKI-based substrates.(ABSTRACT TRUNCATED AT 250 WORDS)
Collapse
Affiliation(s)
- R D Mitchell
- Department of Biological Chemistry, School of Medicine, University of California, Davis 95616
| | | | | | | | | |
Collapse
|
45
|
Soll RM, Dollings PJ, Mitchell RD, Hafner DA. Guanabenz-related amidinohydrazones: potent non-azole inhibitors of aldosterone biosynthesis. Eur J Med Chem 1994. [DOI: 10.1016/0223-5234(94)90040-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
|
46
|
Abstract
The purpose of this study was to determine the magnitude and direction of maxillary and mandibular first molar and incisor changes that occur during Class II molar correction with Wilson "rapid molar distalization." Nineteen patients (13 females, 6 males) were selected from the clinic at Loma Linda University Department of Orthodontics. All patients received maxillary bimetric distalizing arches (BDA), and either a mandibular three-dimensional lingual arch, with or without a passive 0.016 x 0.016-inch utility arch, or a traditional edgewise full banded and bonded arch. The arches were activated with open coil spring and Class II intermaxillary elastics. A total of five activations were completed or until visual inspection revealed a Class I molar relation. Prestudy and poststudy lateral cephalometric radiographs were taken with molar bands cemented. Dental changes were determined, with Ricketts superimpositions. The mean change in molar relation measured at the occlusal plane was 4.1 mm. The mean maxillary molar distalization was 2.16 mm, with 7.8 degrees of tip. The rate of maxillary molar movement was 0.56 mm per month. The mean mandibular molar mesial movement was 1.38 mm. The maxillary incisors protruded a mean of 0.3 mm, and extruded a mean of 1.6 mm. Except for the edgewise sample, all mandibular molars moved mesially further than the incisors, reducing the mandibular arch length. The presence of erupted maxillary second molars did not correlate with the rate of maxillary first molar movement, magnitude of movement, or amount of tipping that occurred.
Collapse
Affiliation(s)
- D S Muse
- Loma Linda University, School of Dentistry, Calif
| | | | | | | |
Collapse
|
47
|
Mitchell RD, Burke WH. The effect of orally administered thyrotropin-releasing hormone on growth and carcass characteristics of seven- to ten-week-old broilers. Poult Sci 1993; 72:1952-60. [PMID: 8415361 DOI: 10.3382/ps.0721952] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
In contrast to some earlier studies with young broiler chickens, several recent studies have shown growth responses to exogenous growth hormone (GH) administration in broiler chickens of advanced age (Vasilatos-Younken et al., 1988; Scanes et al., 1990). It was therefore of interest to determine whether intermittent feeding of thyrotropin-releasing hormone (TRH), a known GH secretagogue, would elevate plasma GH of 7- to 10-wk-old broilers and alter their growth characteristics. Four replicate pens of 15 males and four pens of 15 females 7 to 10 wk of age were given access to feed containing 3.5 mg/kg of TRH for four 2-h periods each 24 h with 4-h periods of feed removal between. Control groups either were fed the basal ration on the same intermittent schedule or had continuous access to it. Growth hormone concentrations, measured 45 to 75 min after the start of TRH feeding periods, were significantly elevated in males on the 1st day of the experiment and after 7, 14, and 21 days when they were 7, 8, 9, and 10 wk of age, respectively. Concentrations in females were elevated on the 1st day of treatment, but not thereafter. Treatment with TRH had no effect on BW or relative gain of males at any time. It significantly increased relative gain of females during the 1st wk, but not thereafter. There were no treatment effects on 10-wk shank length, Pectoralis major weight, Gastrocnemius weight, or liver weight in either sex, but the percentage fat pad of males fed TRH was lower than that of controls fed intermittently.
Collapse
Affiliation(s)
- R D Mitchell
- Department of Poultry Science, University of Georgia, Athens 30602-2772
| | | |
Collapse
|
48
|
Olah GA, Mitchell RD, Sosnick TR, Walsh DA, Trewhella J. Solution structure of the cAMP-dependent protein kinase catalytic subunit and its contraction upon binding the protein kinase inhibitor peptide. Biochemistry 1993; 32:3649-57. [PMID: 8385485 DOI: 10.1021/bi00065a018] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Small-angle X-ray scattering and Fourier transform infrared (FTIR) spectroscopy experiments have been completed on the catalytic subunit of the cAMP-dependent protein kinase. Measurements were made both with and without the protein kinase inhibitor peptide, PKI alpha(5-22)amide. Binding of the peptide results in an overall contraction of the structure that is characterized by a decrease of 9% in radius of gyration and about 16% in the maximum linear dimension. Both the secondary structure content of the protein/peptide complex, as determined by FTIR, and the solution structure of this binary complex, as determined by X-ray scattering, agree well with the structural characteristics of this complex as elucidated by the crystal structure [Knighton, D.R., Zheng, J., Ten Eyck, L. F., Ashford, V.A., Xuong, N.H., Taylor, S.S., & Sowadsi, J. M. (1991a) Science 253, 407-414]. Further, the contraction of the structure observed by X-ray scattering upon inhibitor peptide binding is not accompanied by any detectable change in secondary structure content of the kinase. We have modeled the contraction of the kinase upon inhibitor peptide binding as a simple rotation of the large and small lobes seen in the crystal structure such that the cleft between them is closed. For a substrate these changes would then allow catalysis to ensue. The hinge for this movement occurs around a glycine that is one of the protein kinase family consensus amino acids.
Collapse
Affiliation(s)
- G A Olah
- Isotope and Nuclear Chemistry Division, Los Alamos National Laboratory, New Mexico 87545
| | | | | | | | | |
Collapse
|
49
|
Mitchell RD. Temporomandibular joint eminence augmentation by down-fracture and interpositional cartilage graft. A new surgical technique. Int J Oral Maxillofac Surg 1992; 21:183-4. [PMID: 1640133 DOI: 10.1016/s0901-5027(05)80791-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
|
50
|
Lever EL, Walter MH, Condon SC, Balasubramaniam K, Chen YK, Mitchell RD, Herber R, Collen MJ. Addition of enemas to oral lavage preparation for colonoscopy is not necessary. Gastrointest Endosc 1992; 38:369-72. [PMID: 1607091 DOI: 10.1016/s0016-5107(92)70435-0] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
To evaluate whether the addition of enemas to oral electrolyte lavage is helpful for colonoscopic preparation, we conducted a prospective, randomized, observer-blinded trial to compare oral lavage plus enemas with oral lavage alone. The quality of preparation, mucosal visualization, and the volume of retained colonic fluid did not differ between the two groups. Twenty-two percent of the patients in the group who received oral lavage plus enemas compared with 12% of the patients in the group that only received oral lavage stated that they would refuse to repeat the preparation for future colonoscopic examination. Seventeen percent of the patients in the group that received oral lavage plus enemas demonstrated anorectal trauma or inflammation compared with only 5% in the group that received oral lavage alone (p = 0.09). These results indicate that the addition of enemas to oral lavage preparation for colonoscopic evaluation cannot be routinely recommended. However, enemas may be considered on an individual basis in the occasional patient unable to consume the complete oral lavage or in whom residual stool is found during colonoscopic evaluation after oral lavage preparation.
Collapse
Affiliation(s)
- E L Lever
- Department of Medicine, Loma Linda University Medical Center, California
| | | | | | | | | | | | | | | |
Collapse
|